diff --git a/modules/paapi.js b/modules/paapi.js
index 310974b31fe..8ddd1912c29 100644
--- a/modules/paapi.js
+++ b/modules/paapi.js
@@ -158,8 +158,9 @@ export function addPaapiConfigHook(next, request, paapiConfig) {
     const {config, igb} = paapiConfig;
     if (config) {
       config.auctionSignals = setFPD(config.auctionSignals || {}, request);
+      const pbs = config.perBuyerSignals = config.perBuyerSignals ?? {};
       (config.interestGroupBuyers || []).forEach(buyer => {
-        deepSetValue(config, `perBuyerSignals.${buyer}`, setFPD(config.perBuyerSignals?.[buyer] || {}, request));
+        pbs[buyer] = setFPD(pbs[buyer] ?? {}, request);
       })
       storePendingData(pendingConfigsForAuction, config);
     }
diff --git a/modules/topicsFpdModule.js b/modules/topicsFpdModule.js
index d99696152ba..8df01fcd599 100644
--- a/modules/topicsFpdModule.js
+++ b/modules/topicsFpdModule.js
@@ -130,7 +130,7 @@ export function processFpd(config, {global}, {data = topicsData} = {}) {
 export function getCachedTopics() {
   let cachedTopicData = [];
   const topics = config.getConfig('userSync.topics');
-  const bidderList = topics.bidders || [];
+  const bidderList = topics?.bidders || [];
   let storedSegments = new Map(safeJSONParse(coreStorage.getDataFromLocalStorage(topicStorageName)));
   storedSegments && storedSegments.forEach((value, cachedBidder) => {
     // Check bidder exist in config for cached bidder data and then only retrieve the cached data
diff --git a/test/spec/modules/paapi_spec.js b/test/spec/modules/paapi_spec.js
index 7814c09ea61..77c8a6d7dda 100644
--- a/test/spec/modules/paapi_spec.js
+++ b/test/spec/modules/paapi_spec.js
@@ -91,10 +91,10 @@ describe('paapi module', () => {
           let igb1, igb2, buyerAuctionConfig;
           beforeEach(() => {
             igb1 = {
-              origin: 'buyer1'
+              origin: 'buyer.1'
             };
             igb2 = {
-              origin: 'buyer2'
+              origin: 'buyer.2'
             };
             buyerAuctionConfig = {
               seller: 'seller',
@@ -263,11 +263,11 @@ describe('paapi module', () => {
           });
 
           it('should be added to perBuyerSignals', () => {
-            auctionConfig.interestGroupBuyers = ['buyer1', 'buyer2'];
+            auctionConfig.interestGroupBuyers = ['buyer.1', 'buyer.2'];
             const pbs = getComponentAuctionConfig().perBuyerSignals;
             sinon.assert.match(pbs, {
-              buyer1: {prebid: {ortb2, ortb2Imp}},
-              buyer2: {prebid: {ortb2, ortb2Imp}}
+              'buyer.1': {prebid: {ortb2, ortb2Imp}},
+              'buyer.2': {prebid: {ortb2, ortb2Imp}}
             });
           });
 
diff --git a/test/spec/modules/topicsFpdModule_spec.js b/test/spec/modules/topicsFpdModule_spec.js
index 6bc8eb1e7c3..0f8e379e95f 100644
--- a/test/spec/modules/topicsFpdModule_spec.js
+++ b/test/spec/modules/topicsFpdModule_spec.js
@@ -308,33 +308,6 @@ describe('topics', () => {
       }],
       name: 'ads.pubmatic.com'
     }];
-    const consentString = 'CPi8wgAPi8wgAADABBENCrCsAP_AAH_AAAAAISNB7D==';
-    const consentConfig = {
-      consentString: consentString,
-      gdprApplies: true,
-      vendorData: {
-        metadata: consentString,
-        gdprApplies: true,
-        purpose: {
-          consents: {
-            1: true,
-            2: true,
-            3: true,
-            4: true
-          }
-        }
-      }
-    };
-    const mockData = [
-      {
-        name: 'domain',
-        segment: [{id: 123}]
-      },
-      {
-        name: 'domain',
-        segment: [{id: 321}],
-      }
-    ];
 
     const evt = {
       data: '{"segment":{"domain":"ads.pubmatic.com","topics":[{"configVersion":"chrome.1","modelVersion":"2206021246","taxonomyVersion":"1","topic":165,"version":"chrome.1:1:2206021246"}],"bidder":"pubmatic"},"date":1669743901858}',
@@ -345,49 +318,60 @@ describe('topics', () => {
       storage.removeDataFromLocalStorage(topicStorageName);
     });
 
-    describe('when cached data is available and not expired', () => {
+    describe('caching', () => {
       let sandbox;
       beforeEach(() => {
         sandbox = sinon.sandbox.create();
-        const storedSegments = JSON.stringify(
-          [['pubmatic', {
-            '2206021246': {
-              'ext': {'segtax': 600, 'segclass': '2206021246'},
-              'segment': [{'id': '243'}, {'id': '265'}],
-              'name': 'ads.pubmatic.com'
-            },
-            'lastUpdated': new Date().getTime()
-          }]]
-        );
-        storage.setDataInLocalStorage(topicStorageName, storedSegments);
-        config.setConfig({
-          userSync: {
-            topics: {
-              maxTopicCaller: 4,
-              bidders: [{
-                bidder: 'pubmatic',
-                iframeURL: 'https://ads.pubmatic.com/AdServer/js/topics/topics_frame.html'
-              }]
-            }
-          }
-        })
-      });
+      })
+
       afterEach(() => {
         sandbox.restore();
         config.resetConfig();
       });
 
-      it('should return segments for bidder if transmitUfpd is allowed', () => {
-        assert.deepEqual(getCachedTopics(), expected);
-      });
+      it('should return no segments when not configured', () => {
+        config.setConfig({userSync: {}});
+        expect(getCachedTopics()).to.eql([]);
+      })
+
+      describe('when cached data is available and not expired', () => {
+        beforeEach(() => {
+          const storedSegments = JSON.stringify(
+            [['pubmatic', {
+              '2206021246': {
+                'ext': {'segtax': 600, 'segclass': '2206021246'},
+                'segment': [{'id': '243'}, {'id': '265'}],
+                'name': 'ads.pubmatic.com'
+              },
+              'lastUpdated': new Date().getTime()
+            }]]
+          );
+          storage.setDataInLocalStorage(topicStorageName, storedSegments);
+          config.setConfig({
+            userSync: {
+              topics: {
+                maxTopicCaller: 4,
+                bidders: [{
+                  bidder: 'pubmatic',
+                  iframeURL: 'https://ads.pubmatic.com/AdServer/js/topics/topics_frame.html'
+                }]
+              }
+            }
+          })
+        });
 
-      it('should NOT return segments for bidder if enrichUfpd is NOT allowed', () => {
-        sandbox.stub(activities, 'isActivityAllowed').callsFake((activity, params) => {
-          return !(activity === ACTIVITY_ENRICH_UFPD && params.component === 'bidder.pubmatic');
+        it('should return segments for bidder if transmitUfpd is allowed', () => {
+          assert.deepEqual(getCachedTopics(), expected);
+        });
+
+        it('should NOT return segments for bidder if enrichUfpd is NOT allowed', () => {
+          sandbox.stub(activities, 'isActivityAllowed').callsFake((activity, params) => {
+            return !(activity === ACTIVITY_ENRICH_UFPD && params.component === 'bidder.pubmatic');
+          });
+          expect(getCachedTopics()).to.eql([]);
         });
-        expect(getCachedTopics()).to.eql([]);
       });
-    })
+    });
 
     it('should return empty segments for bidder if there is cached segments stored which is expired', () => {
       let storedSegments = '[["pubmatic",{"2206021246":{"ext":{"segtax":600,"segclass":"2206021246"},"segment":[{"id":"243"},{"id":"265"}],"name":"ads.pubmatic.com"},"lastUpdated":10}]]';