Have Any of You Navigated HSA Territory?

In the MSA with my ex (finalized December 2024) there is a section on healthcare that specifies I must provide her with an HSA debit card, even though she's not covered on my insurance, it's for the little ones. The thing is, she drains it every. single. time. I could have $2400 in there, and she'll ask me to unlock the card she needs to get some mucinex and ibuprofen for the kids from CVS. I'll look a few hours later and it's $670 less. The kids tell me she is buying EVERYTHING at CVS or Target (the ones with a CVS in them).

I have asked her for receipts because Fidelity has asked me for them. And she refused, citing the marital agreement and it doesn't say it is a requirement. I'm fairly certain because non-HSA stuff is being purchased with my HSA account I am going to be held liable for paying it back.

Have any of you faced this situation? What did you do? I'm just looking for some general advice beyond "Go talk to your lawyer." I know I need to do that...but I'm still paying off the last time I "talked" to him.

Thanks!

Edit: This is being provided by request, the wording of the relevant portion in the MSA for the HSA is:

The parties agree that Husband shall continue to contribute to this account for the benefit of the minor children in a monthly amount at Husband’s discretion for as long as he participates in a High Deductible Health Plan (HDHP). As long as the parties are married (through the date of a Judgment of Absolute Divorce), each party shall have a debit card for this account and the parties agree that this account shall be used as needed for payment of the minor children’s ongoing extraordinary medical expenses. Husband shall ensure Wife has a debit card (if the card is updated, replaced, etc.) and provide documentation to Wife within five (5) days of request by Wife for the same to confirm he is complying with this provision and that both parties have access to this account. Husband shall also keep Wife apprised of the balance on this account to ensure that both parties know the available balance of funds.

Edit2: Update: Thanks for all your replies and insights. Thanks to u/boxwood18 for pointing out the obvious: Everything after "As long as the parties are married..." is void now post-divorce. Confirmed by my lawyer. Cancelled her HSA card today, thank God.