This is the top edge of the door when I tried to close it. Seems like the door is too large. I guess the door expanded due to moisture or the frame shriked.

How can I fix?

Thanks!

Have you painted recently? I have a few doors the previous homeowner painted to the point of not being able to close.

A thin shim, like a couple or more layers of cardboard, underneath the top hinge where it is fastened to either the door or the jamb, should angle the door down a bit to relieve minor binding. Loosen the screws a bit, slip the shim(s) underneath the hinge plate and snug up the screws.

If there is severe or advancing binding, do you see signs of the door frame shifting or any cracks in the walls?

Do you have some problems with dampness? I had this issue because of the constant dampness in my house.

There are various ways to deal with this for now. If it continues to happen then you may need to look at structure shifting. For now it may be minor settling.

You can plane the top of the door to fit the opening.

You can shim the top door hinge to make the binding corner drop a bit.

You can take the trim on the top jamb off and use a saw to cut the jamb nails, and re-shim/re-nail the jamb so the door closes.