autofs on ubuntu locking up mounting over a vpn

I am running autofs on ubuntu 18.04. One of the mount points is over a vpn. The issue is that when the vpn is down and a process tries to access a document on the mountpoint autofs can lock up and stop mounting other mountpoints. Is there any way to configure autofs so that when the vpn goes down the other mountpoints are not affected?

When the vpn is up everything works well. When the vpn fails, if it does not recover in time other mounts soon fail too.

Syslog is showing entries like the following:
Nov 10 11:13:07 xxxxxxx kernel: [1542281.518959] CIFS VFS: Server srvr2 has not responded in 180 seconds. Reconnecting...

auto.master looks like this

+auto.master/lfmount/fs1 /etc/client_documents.fs1 /lfmount/fs2 /etc/client_documents.fs2

client_documents.fs1 look like the following:

documents -fstype=cifs,vers=3.0,uid=1001,gid=1001,dir_mode=0777,file_mode=0777,nounix,credentials=/etc/fs1.credentials,_netdev ://srvr1/client_documents/fs1/documents

client_documents.fs2 looks like this - and srvr2 is accessed through a vpn:

documents -fstype=cifs,vers=3.0,uid=1001,gid=1001,dir_mode=0777,file_mode=0777,nounix,credentials=/etc/fs2.credentials,_netdev ://srvr2/fs2/documents