Auth tokens expire, usually in 24 hours. Try sending an AuthRequest to get a current auth token. (Also, why is the auth token being stored in a variable called "cosid"?) Also, surrounding your auth token with '. and .' will render it invalid.
You also probably don't want SearchConvRequest, as that searches within a single conversation. Use SearchRequest instead.
Also, why do you have an <e> element inside a SearchConvRequest? |