Hello everyone. I have some troubles with configuring dual WAN failover on Mikrotik RB750GR3. I use 4G USB stick on the LTE interface as the secondary internet connection, and the regular WAN port for the primary. Both interfaces get addresses from the DHCP and that's all good and working - primary interface gets address from the core router in my company, and secondary gets address from ISP2 4G provider. When I disable interface, it switches over to the secondary. When I re-enable the main interface it goes primary again, that all works good as it should be working (Idea is not to use 4G unless don't have to).

Problem is in this: In experiment in which I make an access list entry on the CORE router (behind the failover router) for the primary address to drop the traffic coming in it stops the traffic, but do not failover to the secondary connection. it makes me think that this whole thing only works with gateway checking, but not the actual public IP? (I monitor 8.8.8.8 and 1.1.1.1)

So far i tried failover with policy routing and script failover. They both worked great with physical issues but when it comes to this test it is not working as it is supposed to.
I tried this setup: https://wiki.mikrotik.com/wiki/Advanced ... _Scripting

Do anyone have any idea how to get through this problem? Or what is the cause of it?

Please show me Bridge and Bridge/Port.
Also, Interface/Ethernet
Thanks