I suggest you to try to submission on a High Quality links to increase the Domain Authority of the website. We have to follow’s the 5 to 6 factors to increasing the Domain Authority of the Website, Usually Authority Score is calculated based on : Backlinks, Referring Domains, Monthly Visits, Keywords.
If you want more, so you can consult with Phoenix SEO Expert.
Here are some off-page SEO activities that you can try
Broken Link Building
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