Basic Always on setup failover issue


I configured the Basic Alwayson setup in two of the test SQL 2017 standard test servers(A,B).
As per basic configuration only one db i am able to add it in group. Configuration everything went well with automatic failover from primary-A to secondary-B once i off the sql services in primary server. Now secondary-B is primary became primary.
I started the sql services in previous A server and off the services in B services.But here instead of failover both servers went to Resolving mode. To resolve this i on the sql service in B server i waited for whole night whether dbs will sync.I even tried force failover but Nothing worked.
Now both servers are in resolving state. Not able to understand what to do now.
The error i am getting as below

the availability replica for availability group xyz on this instance of sql server can not become the primary replica because the wsfc cluster was started in force quorum mode.consider performing a forced manua failover (with possible data loss) error 41125.

I check the WSFC - Ag Role XYZ failed.
Both nodes are up.

Anything i need to check? Please suggest.