On Twitter, Google’s John Mueller said that getting a new domain name won’t help you to get rid of a manual Google penalty.
Just to state the obvious, since the sites are the same, Google will treat them the same & pick a canonical for the combined signals. You don't necessarily need to do a 301 to have it be seen as a site move.— ? John ? (@JohnMu) August 26, 2019
Remove bad links that point to your website
Google sometimes penalized website that build artificial links. Use the link disinfection tool in SEOprofiler to get rid of these unnatural links: