Have you actually SEEN what she received?

My first guess is a potential scam ... they want her to pay a processing fee or something like that.  Or possibly even just an advertisement or political flyer.

Real - no, scam - definitely.  First the program was stopped by the courts.  Then the limit was $10,000 per student borrower.

Did the letter come from an attorney in Nigeria who is looking for someone to cash the check for the crown prince?

Yeah, I wouldn't rush down to the bank to cash that check.  Usually loan forgiveness means they send you a friendly little letter saying "you don't owe us this amount anymore", they don't usually send you more money.  Out of curiosity, who is the check supposedly from?

@IRonMaN "Out of curiosity, who is the check supposedly from?"

My guess:  The Royal Nigerian Bank of Lagos

It's not forgiveness and not a scam. However, it is consumer misdirection.

The loan servicers are sending checks to those who paid off their loans. That way, the borrower is back in debt and now, they have the money while they wait for forgiveness. In other words, they just borrowed their own repayment, and now are on the hook for the forgiveness, which will go back to the loan servicer, who also makes more interest on these new debts. They've turned school loans into revolving credit.

Yes, it appears that those who made payments during the Covid-19 suspension can ask for their money back (did the client do this?) and have it added back to the balance.  It's not forgiveness, it's a return to the balance owed before the payments were made. 

https://www.nerdwallet.com/article/loans/student-loans/refund-student-loan-payments

"can ask for their money back (did the client do this?)"

What is happening is the loan service provider your client worked with, is contacting them with "forgiveness" paperwork. It looks real. It isn't forgiveness paperwork, though.

"U.S. Supreme Court justices have scheduled high-profile arguments over President Joe Biden's student loan forgiveness plan for Feb. 28."

And it never was $40,000 for one borrorwer:

"Biden's plan would cancel up to $20,000 in student loan debt for Pell Grant recipients, and $10,000 for other borrowers, for people earning up to $125,000 a year or part of a household where total earnings are no more than $250,000."