What could be the reasons for not attaching files?

Question

Yii

I have a problem. the fact that today I don’t have files attached to the database, of various types. Although the files are 6.9 mb. Basically, it's not that big. Is this a server side issue or not?
Although on other days everything was fine. That goes out, you attach it, you click on the submit button of the form and the page loads for a very long time and an error occurs that the waiting time has been exceeded