I received social security in 2019 but I didn't receive a form SSA 1099 to add this income to my 2019 taxes

You may not have received your 1099-SSA form yet, but should by 31 January.  If you do not here is a link with information on getting a replacement form.   

I was told by Social Security agent that I will not receive a form 1099 this year because all of my SS benefits were used to pay for Medicare premiums. I can't get through to local office.

You can use the amount of medicare premiums to enter your social security and you must enter the same amount under amounts paid for medicare. A document (SSA-1099) is not necessary if you know the amounts. The following link will provide standard medicare benefits for 2021, if you were not required to pay a higher amount.

• SSA What is the monthly premium for medicare part B in 2021?

You can also set up an online account to view your information by using this link: My Social Security Account