If i get my amended return back due to supporting information being incomplete what do i do?

[tommyknol]

I got a letter stating my amended return couldnt be processed due to supporting information was not complete. I did everything online so i dont know what i missed. Anyone have any ideas?

[Critter-3]

Read the notice carefully and supply the information requested as directed in the notice even if you think it was already provided.  Until you comply with the request the amended return will not be processed.