Old link anchors causing problems?

So here is my problem:

I bought a domain with a lot of backlinks which almost all use the name of the website as the anchor.

The plan was to build a website on this domain, but I came across a better name.

So what I did was build the website on the new domain and do a 301 with both domains added to my Search console.

Now after some months the new website is hardly ranking for anything.

When i check my website in AHREFS almost all backlinks have the domain/brandname of the old domain in them.

Could the old 301 domain be the issue? As almost all links for that domain have the brandname/website in them?

Anyone?

That must be because the references of your links go back to the old domain, and that's what's being tracked by AHREFS instead of the new one. In any case, check out this link https://www.hallaminternet.com/switch-domains-losing-traffic/