Missing one of the two providers on mikrotik rb2011 in different subnets?

Question

network hardware

Good day.
You rarely have to work with the products of this company, but if you are given non-standard tasks, then for some reason the choice falls on this company, so in my case they gave the task: to bring 2 different Internet lines to the floor, in one wing of the Internet "red" in the other wing of the building Internet blue. In general, after thinking, I chose a piece of iron from Mikrotik and started smoking the Internet, found an article, adjusted it to my needs and since 2019 everything has been working properly, but literally 3-4 days ago the "blue" channel falls off.
Stopped sharing traffic i.e. mikrotik works only on the "red" channel, I double-checked everything, no changes were made, the firmware was not updated, in general, nothing was touched, I broke my whole head, I can’t understand what the reason is, I’ll say right away don’t judge strictly, I’m self-taught in setting up mikrotik and I ask for your help point out my problem or give a hint.
Those. data:
There are 2 Internet lines from Rostelecom connected via PPoE, red-static line, blue speaker line, red traffic goes to the network 192.168.6.1 and to the network 192.168.10.1-for third-party users, blue goes to the network 192.168.7.1
general information:

interfaces:

Thank you in advance, ask me to share what screenshots you need.
If necessary, I will throw off the link to the article on which it was configured in 2019.
I will also reward you financially for your help.

Answer 1

In general, as usual, he asked himself and answered, 8 hours of picking and the problem lay in one checkmark, namely passthrought in the settings of the mangle rule rules, it had to be removed for a number of rules.

Answer 2

Does the ISP's gateway ping with Mikrotik?
Have you tried to leave only 1 channel by default?
Well, stupid - is everything ok with the provider, is the Internet paid)