After transferring all whole shares from my Equiniti SEP-IRA custodial account to another SEP-IRA custodial of mine at Etrade, I was issued and inadvertently cashed a residual dividend payment from Equiniti (which was made out to my name, but with the custodian designation as well), which reflceted a dividend payment that occurred after the share transfer date. Equiniti then issued me a 1099-B, when it should have issued a 1099-R to me reflecting an IRA distribution. But Equiniti says it cannot/does not issued 1099-R forms. How do I fix or explain the erroneous form to the IRS?
You received a residual dividend payment, which can be reported on Form 1099-B. If it had been deposited into the new SEP-IRA, you could have reported it as an IRA distribution. In this case, you will need to include the dividends on your tax return.