UDM Pro site to site VPN

Hi i have two sites both running a UDM Pro at each end connected to the same ui account. I have tried to setup a site to site VPN between the two using manual ipsec and open vpn to test both. I cannot get the manual ipsec to work and the openvpn connection works and pings but something is blocking the traffic. So if someone at site B wished to access documents on site A it wont let them. Both sites run VLANS on different subnets. Any help or info appreciated. Thanks