Why do records disappear from the database?

Question

MySQL

Hello, there was a mystical problem!
I’m making a website on codeigniter and this is how records from the database began to disappear for two days, then from one table, then from another, then one at a time, then several pieces. Half a day may not be deleted at all.
It feels like someone is deleting it.
Only me and the client have access, the client did not do this. no benefit to him.
Hosting support also respond that everything is fine with them.
Although before that they had some kind of caching and it interfered with editing the site (it took a long time to wait for changes) and they turned it off, and then this trouble began.

Answer 1

I tied the deletion to the session and everything was fine. Although the reason is not known

Answer 2

well, either you or the client deletes what is there to think then

Answer 3

create a delete trigger, fix the date and user, write a table to the log

Answer 4

make a request log and see when and what request was
then I think you will understand

Answer 5

Turn off web server logs, database logs and see who, what and why.
Maybe you have a security problem there.

Answer 6

Maybe foreign keys are not configured correctly and when a record is changed, related ones are deleted ...