I too received this invoice after several years of no fee service from Prudential.
I have an IRA rollover from a former employers 401K plan with them. I have made multiple calls requesting a copy of the fee schedule and argued that I never saw such a document which I was initially told mailed separately in March.
As of today, I learned that it was included with the March statement, but when I checked the online version of this document, there is only a small side note mentioning revised fees, but no insert. I will call again to request a copy of the insert, as I would like to file a formal complaint.
For now, I am working on closing the account and transferring the funds to another institution for which there will be another $100 close out fee.
Prudential will never see another dime of my money.