Domain reputation, or how your domain is perceived by mailbox providers, is a key component in email deliverability: mailbox providers use it to make decisions about whether your emails should make it to the inbox or not.
There are many ways to monitor your domain reputation but the most reliable one is Google Postmaster as Google is a top receiver for many senders, and you can check your domain reputation in Google Postmaster Tools (GPT).
If any doubts or errors come up, kindly refer to the below provided link.
https://support.google.com/mail/answer/9981691?hl=en-GB&visit_id=638211274353273880-3180064304&rd=1