How to get HUAWEI 5G CPE Pro 2 to work with a Balance_BB54

Has anyone setup a HUAWEI 5G CPE Pro 2 with a Peplink firewall as a failover line on WAN2. We cant get the internet traffic through the peplink.

Just using the HUAWEI 5G CPE Pro 2 and a laptop, it works fine.

We have tried so many ways:

  1. Using the HUAWEI 5G CPE Pro 2 on WAN2 using DHCP and double natting
  2. Tried the HUAWEI 5G CPE Pro 2 in bridge mode and still no luck

Any advice will be gratefully received.

Thank you in advance