Why are wordpress theme files being deleted on their own?

Question

WordPress

Hello, tell me please.
After uploading the site to the hosting, after about a minute, the functions.php file and some other files are deleted from the theme folder.
Tell me how to fix this, what files to provide to solve this problem?
I tried to figure it out myself, but did not understand how to solve the problem ...
Thanks in advance!

Answer 1

I can assume that you have malicious code in functions.php, and some script on your hosting automatically removes it. If you have installed premium plugins and themes on your site (for free), then they usually come with a bunch of malicious codes. especially in functions.php
From here, the solution is to clean up the site code, and then upload it to the hosting