"Why would they take this amount out of my account?"
We in the Community have no way of knowing why your HSA custodian did this, nor whether or not it was a mistake. Perhaps they were just fixing something else. Perhaps it was rooted in a management fee for 2 or 3 months (administration fees can be removed from your account, but do not count as a distribution).
"They placed a dollar figure amount into my HSA that did not match my payroll deduction. " I am familiar with this situation...but in my case, it wasn't the HSA custodian's fault...it was the 3rd party benefits processor my wife's company uses...they made mistakes more than once and they fix it when the error is pointed out...usually.
"Is there an institition (sic) that firms representing HSA accounts report to?" These firms are generally banks or other financial institutions, regulated by the state or the federal government. However, I suggest that your employer, if large, probably has more ability to get the attention of the HSA custodian. Have a talk with your benefits administrator.
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