After upgrade from couchbase 4 to 5 - cluster is stuck in 4.5 compatability mode

After upgrading my 7 node couchbase cluster from 4.6.1 to 5.0.1 community edition I get this message in the browser window:

This cluster contains multiple server versions and is running in 4.5 compatibility mode.

I get these errors in the logs. Specifically a bucket called user on a specific node. I’ve tried removing nodes and adding them back into the cluster and the error moves to then to another node. Eventually coming back around to the same node again.

Unsuccessful user storage upgrade.
{gen_fsm,handle_msg,7,[{file,“gen_fsm.erl”},{line,505}]}]} (repeated 8 times) hide

How do I fix this?

I fixed the problem. I set up the cluster again and restored from backup.

I would like to point this out. NEVER alter any settings during an upgrade process. I mistakenly set a read-only user while performing an upgrade. Don’t do this! It breaks the upgrade. Wait till the upgrade has fully completed first.

i didn’t do any changes while upgrading but still facing this error .
what is the procedure to fix this,