Just checked the blacklisting, now it has been removed. A few hours ago it was still listed. As the status of lists can be cached for performance reasons , give it a few hours and try again.
You can also try and look into the google postmaster tools to get a better reputation there. Don’t just monitor your ip, but also your domainname. I checked what domains are registered on the mentioned ip, and it seems the domain medicarrier.in is only 2 months old. Getting blacklisted within 2 months can give a bad reputation for that domain. Also the age of a domain can play parts in positive or negative scoring of e-mails.
Getting e-mail trough the google filters can be tough.
Make sure your ip is clean and doesn’t have a bad history. The previous user can have messed things up.
Get and maintain a good reputation on your domain, make sure spf, dkim etc is all configured correctly.
Make use of the tools google provides to get your domain accepted
As written by mlcwuser , maybe look into another isp.. Checking yours , elyzium , they don’t default redirect to https (ssl). Bit funky for an isp to neglect that. You can also contact them and ask if they have a e-mail relay infrastructure (make sure you adapt your dns settings to reflect this).
Testing another isp (hosting provider) can also be worth trying. Choosing a huge one like AWS can be a beast to get a good pricing choice, but you can also look into one of the bigger ones in Europe like Hetzner or Contabo and test a vps for one month (price below 10 euro).
This is no issue with mailcow, so the support options are limited to suggestions from users on this forum. Just some bad luck with your ip / hosting provider and the spamfilters of google.
just my 2 cents.
