AcquireTokenSilent method providing a new accesstoken everytime even though it hasn't expired yet

Question

I am using angular and trying to implement azure ad b2c connection. But for accessing an API I am calling acquiretokensilent to get the cached token. But it is providing me a new set of tokens every single time even though the accesstoken hasn't expired yet. Here is the code.

getDataFromjQuery(){
    var account = this.authService.instance.getAccountByUsername('[email protected]');
    const accessTokenRequest = {
      scopes: ["https://*********.com/api/FullAccess"],
      account: account || this.authService.instance.getAllAccounts()[0],
      forceRefresh: false,
      cacheLookupPolicy: CacheLookupPolicy.Default,
      refreshTokenExpirationOffsetSeconds: 7200
    };
    this.authService.acquireTokenSilent(accessTokenRequest).subscribe( (accessTokenReponse) => {
      if(accessTokenReponse != null) {
        // Acquire token silent success
        let accessToken = accessTokenReponse.accessToken;
        // Call your API with token
        console.log("We got the token! hahaha: " + accessToken);
  
        const headers = {
          Authorization: `Bearer ${accessToken}`,
        };
        $.ajax({
          url: this.apiUrl,
          method: 'GET',
          headers: headers,
          dataType: 'json',
        }).then((data)=>{console.log(data)});

      }
    })

I am expecting to get new accesstoken only if the current one has expired. But it is providing me a new pair without even checking the cache.