Help understanding charge on health insurance bill, premium tax credit related

Hi all

My husband gets his health insurance through the marketplace. They have deemed him eligible for up to $254 of the premium tax credit. We previously were taking $129 worth. When I go to the healthcare marketplace website, it says his insurance plan is $421. We recently decided to change the amount of PTC to $0. This is because for the past 2 years we have simply had to pay it back at the end of the year come tax time, so that sucks. So on the healthcare marketplace website it says his plan is $421 + $0 in PTC.

We got the first health insurance bill since making this change. Previously his bills would simply say "Benefit -> medical," the coverage dates, and "premium -> $292." On the top of the bill it has a line that says "advance premium tax credit -> $129." This new bill has the same lines, and now the premium says "$421." However, there is a new line on this bill that says "benefit -> ADJ medical", "coverage dates -> 4/01/24 – 5/31/2024" "premium -> $137.60." And now on the top of the bill under "advance premium tax credit -> *-*137.60. " Now the total bill is $540 (rounding a little).

So to sum up: recently changed our advance PTC to $0. New bill now says the advance PTC is a negative amount. This negative amount is being charged to us under the charge "ADJ medical." I am very confused what this could be. I understand that changing the PTC to 0 would mean paying more, but I thought it would be the $421. I hope my explanations make sense, happy to clarify as needed. I will call the health insurance on Monday, but I've worked everyday since getting the bill and it's just driving me nuts. I budgeted for the $421, not $540, just frustrating getting a surprise $140 bill. My husband hasn't been the doctors or anything during this time either, so I don't think it could be anything like that. I appreciate any thoughts on the matter.