Hi,
I'm having an issue in routeros where I'm trying to bring up a second bgp peer. When I enable the second peer that peer establishes for a second then eventually times out with hold timer expires. If I disable the first peer that is receiving 430 routes and enable the second peer it stays up fine with no issues.

It only seems to happen when I have both peers enabled at the same time.

Any idea what would be going on?

I've turned off any firewall when this is happening. On both devices.

What RouterOS version and hardware?

Do you have separate directly connected (e.g. /30) networks for both peerings?
Or is it some sort of multihop setup?
In that case, your first peering is probably adding a route for the network you are using for the second peering.