Get previous next post link from same category

Hello.
I have a website with Envo Magazine theme. The previous/next links in the bottom of all articles (default function in envo) are opening previous and next posts of different categories than the posts have. So my request is to to use that links to navigate in the same category of the article. I’ve tried to find the way to modify that function in the child theme, but no results.
Please have you any suggestion to solve this without plugins?
Thank you!

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