After you file

The IRS system has turned over to the 2021 tax season. That’s why you are getting different information. 
Amending now for that credit is not recommended. It WILL create problems for your current refund of premium tax credit and the 2021 return. 

These are not normal times. The IRS is frankly

ill equipped to process the volume of returns it’s been dealing with the past two years. You can thank Congress for slashing their funds repeatedly. 
I know it’s frustrating to think there’s nothing you can do but it’s a waiting game. Those corrections are done manually and the IRS is understaffed as well. 
I’ve been doing taxes over twenty years and have never witnessed such a disaster. But I saw it coming when the IRS system got overwhelmed last season so I expect the same nightmare this season.  Try to hang in there it’s coming.