How to resolve problem of save button?

Hello

When I edit a file and click on "save", save button doesnt work. Page was load but a file doesnt save. What is the problem for? How can I resolve it?

please explain more detailed

After changing wp-config information, then if i click save button, then  again if i check it, then i can see that its not saved. i have tried many times, but updated documents are not saving

have you tried to disable File System Lock ?