I would send a copy of what was returned back to the VA. Hold on to the original Statement in Support of Claim(Informal Claim) that the VA mailed back to you along with the letter. Did the VA stamp the 21-4138 before they mailed it back? if so, that's good news. It's proof that it was recieved and the VA will have to honor the claim from that stamp date even if they mailed it back. The VA did the same to us. I battled with them and in the end they had to pay from that original date because I saved the 21-4138 that they stamped and mailed back. They said they never recieved it, but I had proof that they had! The informal claim doesn't require much info, so I doubt yours was incomplete. I know ours was not. Good Luck
Yes, they did stamp the 21 -4138 and the back of the form 21-0845. I made a copy of the stamped forms and the letter and sent the originals back. I didn't read your post until after I mailed the originals (certified mail). I thought about keeping the originals, but the letter specifically said return original copies with letter. I was afraid that if I did not do as directed it might cause a problem.