Forgot address on SASE

[purplefreak3]

I sent a item to Canada from the United States and I included IRCs and envelope for return mail but I remembered after I already mailed the package and got home that I forgot to write my address on the return package. My name and address are on the outside package and is on the custom form. Well the person/agency be nice enough to look at the return address/custom form and write my address on the package to return it to me or will it become lost mail aka never get a reply back?

It was sent to Play Management, Inc. if that any help.