PostgreSQL v13 Streaming Replication Issue

Question

Using PostgreSQL v13 streaming replication setup between a primary, and secondary (Hot Standby) server. After maintenance reboots of each server were complete, the secondary (a read-replica) is stuck in recovery mode with a status=streaming. This event has caused a failure in the replication of data. Is there a graceful way to recover? Any help is greatly appreciated.

I have reviewed configuration setup, and files ( postgresql.conf & pg_hba.conf ) are correct- Replication was working prior to reboots.

Logs on the Hot Standby (Secondary) indicate-

• consistent recovery state reached at 0/177B5D8
• invalid record length at 0/177B5D8: wanted 24, got 0
• database system is ready to accept read only connections
• started streaming WAL from primary at 0/1000000 on timeline 1
• could not receive data from client: An existing connection was forcibly closed by the remote host. This seems to make sense, since it is a replica (Read-Only) and the data to be written to the replica fails.

Standby.signal file is present in the Standby servers data directory- Can I just remove the file and restart PostgreSQL service? Or, do I have to promote the Hot Standby to Primary (What do I need to do with the current primary?) to let it recover fully?

Again, any help would be appreciated. Thank you in advance, for any time and consideration regarding this issue.