Question a prior tax filing

For my 2021 1040SR, prepared and submitted with Turbo Tax, the IRS sent me a notice that the Recovery Rebate Credit was wrong and lowered my refund $1,400, from the $5,184 Turbo Tax calculated to $3,784.  I'm wondering if this was a error on my/Turbo Tax's end or with IRS.  Is there any way you can check this?