ManagedDB not respecting our timeout settings; SSL connection has been closed unexpectedly

We are trying to refresh a materialised view that is going to take roughly 20 to 30 minutes because of huge data set. Since refresh view query does not return anyting so connection is forcefully being killed/closed by managed postgres 11 databaes with the following error message.

FATAL: terminating connection due to administrator command
SSL connection has been closed unexpectedly
The connection to the server was lost. Attempting reset: Succeeded.
SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, bits: 256, compression: off)

We have tried a lot (eg. I have tried to connect connect via bare postgres-client and ran the commands there by bypassing any GUI tool and app ORM etc.) and nothing sounds working at all. Can you please help us in this regard.