By calling our national toll-free service at 1-800-772-1213 (TTY 1-800-325-0778) or visiting your local Social Security office. You must go to your local Social Security office and fill out an application form.If you wish to begin a new support case or reopen an old case the following documents are required to be completed and submitted to Montgomery County DRS. Your full spouse's benefit could be up to onehalf the amount your spouse is eligible to receive at their full retirement age. If you need legal help with alimony matters, call a Montgomery County spousal support lawyer at Law Offices of Sheryl R. Rentz at (610) 645-0100. If you are more than one year past full retirement age, go to question 14. Spouse's Social Security number (If none or unknown, so indicate). 13. Montgomery County Child Support Administration, 51 Monroe Street, Suite 811 Rockville, Maryland 20850. Hours of Operation: Monday-Friday: am – pm. The forms can be completed online and then printed out.