Let’s confirm:

Firmware 3.x only support the first item in AllowedIPs settings. If you need to have multiple items in AllowedIPs, you may need to use vpn policy.

We solved this problem in Firmware 4.x. So if you use a router which there is Firmware 4.1 for it, pls try.
If still not 4.x firmware (e.g. SFT1200) pls use vpn policy.