Mine is gone too and have a topic 152 still processing, what I have been told is, if you put anything on line 30 it went to error and don't expect for 8 to 10 more weeks.
Thank you- there is nothing listed on line 30 for me and I got both stimulus checks.
Line 30 on Form 1040 is where any Recovery Rebate Credit is entered. If you received both stimulus payments as expected, no further adjustment will be seen on Line 30. This would not send your return to an error queue with the IRS.
If it has been more than 21 days since you filed, then there may be some other reason for the delay.
For more information, see: