Please be patient. The IRS is still backlogged with 2019 returns. Did you file the 2019 1040-X by mail?
Per the IRS:
COVID-19 Mail Processing Delays
It’s taking us longer to process mailed documents including:
- Paper tax returns, and
- All tax return related correspondence.
We are processing all mail in the order we received it.
Do not file a second tax return or call the IRS.
Also see:
IRS Backlog: 2.4 Million 2019 Tax Returns Still In Pipeline (forbes.com)