Integration Gitlab+Telegram

Hi all.
Has anyone encountered this situation:
it was necessary to set up a telegram newsletter about the completion of the autotest run (it doesn’t matter whether it was successful or not).
I set up a telegram bot and added it as an admin to the notification distribution channel, configured everything in GitLab, Test Settings are successful, the distribution trigger is A pipeline status changes. But the channel does not receive messages for all completed pipelines; a message about the completion of the same autotest with the same tag and run result may or may not arrive. I still don’t understand where to dig next, there doesn’t seem to be much to tinker with in the GitLab settings, maybe something else needs to be configured in the telegram itself for the bot and for the channel?
p.s. I’m not very knowledgeable, I did everything in Gitlab through Integration Settings, maybe it’s better to try through Webhook?
And i tried to set up it in gitlab-сi.yml but no result (((