Connecting to Bridged Modem/Router Web Admin Page through WAN PPPoE

My current setup:

ISP Router (Bridge Mode) connected to WAN Port of Unifi UDM Base, then connected to the internet with PPPoE.

ISP Router IP 192.168.1.1/24.

UDM IP 192.168.0.1/24.

Since the router is in Bridge mode I can no longer access the settings for the router through 192.168.1.1. I’ve looked at many threads here that had the same problem as me but I couldn’t find a solution that works. Can anybody guide me on how I can connect to the ISP Router GUI control panel again through the UDM?

Thanks in advance.