Get your taxes done using TurboTax

the IRS should be sending you a letter explaining the difference. normally this takes 2-3 weeks.  these are not normal times.  your only other option would be to call the IRS

800-829-1040

First choose your language.

Then 2

Then 1

Then 3

Then 2

When asked for SSN  do nothing it will ask twice

Then 2

Then 4

the IRS phone lines are extremely busy presently.  you may not get through so you'll have to keep trying or wait for the letter