Why did you lose access to the network behind GRE?

Question

Mikrotik

Good day! The other day I updated my tiki to version 6.45.6 and lost access to computers behind GRE tunnels. There is a ping on any car in the neighboring network, but it is impossible to fall on it through the same RDP. Nearby there is an IPIP tunnel, it works fine, but GRE does not want to. Updated from version 6.44.X and something became uncomfortable))) Who will tell you what the trouble is?

Answer 1

/ip firewall raw add action=notrack chain=prerouting protocol=gre

from here