Is it okay if I ask another question? in relation to changing my address. Can you assist me with a special number because I am deaf?
Sure, no problem.  If you are deaf or hard of hearing , [23] call our toll - free TTY number , 1 - 800 - 325 - 0778 , between7 a.m. and 7 p.m. Monday through Friday
please explain what the letter is?
The benefit verification letter , sometimes called a benefits letter , or a Social Security award letter , serves as proof of your retirement , disability , Supplemental Security Income SSI , or Medicare benefits