[get error while checking for update]

hi there

been using mautic for almost 1 year now.

Your software
My Mautic version is: 2.15.3
My PHP version is: 7.3

Your problem
My problem is:
lately my campaign is not sending out email (broadcast)- created simple campaign to a segment with more then 1000 contact. Usually it works fine (2-3 month back).

strangely, it works for optin campaign with small volume 20-40 optin a day.

tried to update to latest, but got this error/warning

hope someone can shed a light how to solve this.

These errors are showing in the log:

there is one error i think its not related (not sure)

[proxy_fcgi:error] … /home/runcloud/webapps/mail/app/bundles/CoreBundle/Entity/IpAddress.php

Steps I have tried to fix the problem:

tried clear cache, update database schema, still not solved