Help!

I seriously need a glass of champagne, and somebody to rub my aching head, , and feet.  I am having a lot of problems with a story I am trying to help someone with.  Every time I edit the story and go to save the chapter, the revisions are not showing up at all!  The chapters keep reverting back to the original.  This bothers me because in the comments section people are mentioning the errors.  I have gone back and edited the chapters two, three, and four , or more times.  The last chapter I spent over two hours correcting it, and when I saved the chapter it reverted back.  I literally want to scream!  I also feel bad for the readers, and for the person who is writing the story because the corrections are not showing up, and I cannot as a result get a good idea of anything that I have corrected that might need additional work.  Here is what I am doing.

1.   I hit the button for 'edit chapter' located toward the bottom of the page.

2.  I spend a lot of time editing the chapter.

3.  I hit the button that says 'save'  that is located toward the bottom of the page.

4.  I go back to check, and the changes don't show up.

I've gone back and spent half of my night redoing the revisions, only to go back the next day and find that they are not showing up.  So any suggestions anyone can give me would be most appreciated.  Thanks.