MariaDB Galera Cluster not replicate data after crash

I setup galera cluster on two different server and sync them as a master-master replication.

SERVER CONFIGURATION

Debian GNU/Linux 7 500 GB HDD

Lets say example i have two servers. Server A and Server B

ISSUE

Now due to some reason if server A Mysql crashed or Server Down that time complete traffic managed by Server B and it log data on B server A and server B are in master-master replication so both node are masters.

Now the problem is when A was down and the data which inserted on B that's replicate on A completely fine when A is UP but the data is not sync which perform update operation on B in absence of A.

Does anyone have any idea why this is happening or is there any configuration that resolved my issue?

Thanks in advance.