fee disclosure didn't include all fees

The fee disclosure that was provided to participants  didn't include all the TPA fees being deducted from participant accounts.  I can't find anything that addresses what the correction procedure is.   Can anyone offer direction? 

The fiduciary loses 404(c) protection. There's nothing to fix except to provide the correct disclosures as soon as possible. And hope the participants aren't feeling litigious.

The fee disclosure probably doesn't have the same deadline as stuff like safe harbor or automatic enrollment notices, as well.  So you can run with that and update the fee disclosure notice.

Isn't it potentially a prohibited transaction Covered Service Provide and Plan Fiduciary to take undisclosed fees as the DOL deems the undisclosed fees unreasonable?