Google Index Issue Due to Domain Change

[ABgamesXO]

Years ago, I had opened a website. I had published 8-10 pieces of content on my site. It was receiving good indexing and the number of visitors was great compared to the number of articles. However, due to financial reasons, I couldn't renew the domain and had to back up the database and close the site. About a year later, I wanted to reopen the same site with a different domain. I uploaded the old articles from the backed-up database to the site again. However, despite the articles being indexed, they remained at very low rankings. The articles that used to be indexed on the first page of my old site are now being indexed around the 100th position. As I mentioned, since my old site was closed, I couldn't redirect the links to my new site. Most likely, Google is perceiving my articles as duplicate content. However, my articles are 100% unique. I don't quote from any other sites. I either draw the images myself or edit them from foreign sites. I have never bought any paid backlinks for my sites so far, and I don't plan to do it out of principle. But if I can't solve this problem, I'll be forced to buy backlinks. Do you think acquiring the old domain back and redirecting it to my new site would solve the issue? How else can I solve this problem through different methods? Do you have any suggestions on this matter?