I can’t set up Internet reservation in Mikrotik, what’s the problem?

Question

network hardware

The problem seems to be very simple, but I can't figure it out.
I set up automatic channel switching on MKikrotik. 2 interfaces from 2 providers both have static white IP, ether2 - main, ether1 - backup, with two default routes, with different distances:
Ether2 distance -2
Ether1 Distance -3.
I check the availability of the Internet by pinging Google and Yandex.
And here is the strange result:
I ping via ether1, with the default route eher2 - pinged.
I change the distance of the Ether1 route to 1 (it becomes the main one)
I ping through ether2 - it does not ping.
Why?

Answer 1

https://www.youtube.com/watch?v=Gwl-0bRxOY4

Answer 2

From the most obvious:
1. Select 2 ip on the internet, which will ping to determine availability, for each channel at one address.
2. Register static routes to each of the selected ip, through the appropriate provider. Those. addresses must be pinged without a prescribed default gateway (default), and each of them through its own provider channel.
3. Next, the task is to install default gw on the main or backup channel, depending on the results of pings. Moreover, for the correct operation of nat, it is desirable to clean up already open nat connections when switching the channel.

Answer 3

config show

Answer 4

You don't need to set up metrics. (He himself broke off on this.)
If the main channel at Provo falls, but its gateway is available, then nothing will work for you.
What you need can be done through NetWatch with scripts like these. (That is, disable and enable the necessary routes.)
/ip route set [find comment="ISP2"] disabled=no
/ip route set [find comment="ISP1"] disabled=yes
after marking the routes beforehand. Search the internet for details.