After connecting cloudflare, Ya.Metrika often writes that the site is unavailable, how to solve it?

Question

Yandex.Metrica

A site on a tilde with a customized Yandex metric. Previously, the domain was on reg.ru, everything was fine, then the domain was transferred to cloudflare, and Yandex Metrica started sending notifications about 20 times a day that the site was unavailable and after 5 minutes it was available again. Why so, how to fix this problem?

Answer 1

first, check if there are firewall rules on the cloud and if under attack mode is enabled.
then, if there is nothing like that, then you need to create a rule in the cloud firewall to allow all connections from ip yandex metrics or just from the yandex grid