Hi,
I request you to please let me know that you have created Site to Site VPN between RV042 and RV320 or betweeen RV320 and RV320 on both sides.
Also if you are able to reach out to the WAN IP of the remote side and was not able to ping the LAN Subnet, then you need to check the subnet mask of the LAN IP addresses configured in the VPN.
Also , please call our tollfree number so that a case can be opened and an engineer will work with you to resolve the issue.
https://www.cisco.com/c/en/us/support/web/tsd-cisco-small-business-support-center-contacts.html
Please mark this helpful if it resolves your issue.
Regards
Ritesh Sharma