Could be that the IRS is overwhelmed and way behind.
You may try "Where's My Refund" but even that does not seem to be working properly.
See this info
The IRS is seriously backlogged due to all the extra stimulus filings, as well as a few million unprocessed 2019 returns left over from the COVID shutdown. Contacting them will not help, and the IRS has implored taxpayers not to call them. Lots of other folks are still waiting, so please continue to be patient. Also see:
The IRS is under serious stress — what does that mean for your refund? (msn.com)
What led to IRS backlog: ‘Thin workforce,’ new pandemic relief programs | Federal News Network
The IRS is sending out Stimulus #3 payments in batches, and will take a few weeks to complete them all. This one comes to you separately (and automatically), not as part of your 2020 tax refund. You can check the status here: