Why, if the default route goes through the 2nd port of the Mikrotik 2nd provider, the ip of the provider on the 1st port is not available?

Question

Mikrotik

The essence of the question is as follows: Microt is included in ether 1- ISP1- ip 1.1.1.1, ether2- ISP2- ip 2.2.2.2. Initially, the default routes were: priority 1 through ISP1, priority 2 through ISP2. At the same time, ip 2.2.2.2 was available and the services on it were available. As soon as the priorities of the default routes were changed: 1 priority for ISP2, 2 for ISP1, i.e. ISP1 has become a backup, ip ISP1 has stopped pinging, although the interface itself is enabled. Question: why did this happen? How can I make ip ISP1 accessible again, while it must remain a backup? Thanks in advance for your help
PS
Firmware RouteOS: 6.45.7

Answer 1

https://habr.com/en/post/186284/