Let's remember that their intent was good, but they either did something wrong or got bad guidance or both, it seems.

You have a 1099-R, and it would have code(s).

Here is what it seems is going on:

They put money into a Traditional IRA. Are you treating it as nondeductible or attempting to be deductible? That matters. If they don't qualify for Deductible IRA contribution, and they don't qualify for Roth contribution, and they are using either scenario, that needs to be a correction.

If it is Nondeductible, then the move to Roth should have been conversion. Not recharacterization. The difference is that Recharacterization is trying to state, "Oops, I put into my Traditional IRA and I meant it to be Roth IRA contribution."

But, backdoor Roth is, "I intentionally put a nondeductible Tradition IRA amount and want to immediately convert that to Roth." Conversions are not restricted.

However, if they have other non-basis Trad IRA funds (I think SIMPLE, too; I'd have to read up), then the Conversion will be pro-rata and taxable. The reason backdoor Roth works is where there are no other deferred funds, so that the amount put into Trad IRA (nondeductible = basis) and immediately transferred or rolled (so earnings are avoided) = nontaxable event.

The issues are, then, did they intend to do something deductible? Did they intend to do something not taxable? Did they fail at both attempts?

The broker should be able to help straighten this out, and you have to the filing date of the return to do corrective distribution (take it all out). It also is possible to allocate contributions from one year to another, but it seems they made an ineligible contribution in both attempts?