Either the IRS is incorrect or you were incorrect about the PYEI amount and the IRS caught it. If you mailed in the return it could have been a data entry error by the IRS clerks. Read the IRS notice carefully and respond to it if needed and explain your objection by providing supporting documentation. You may want to seek local professional assistance or you could try the TT audit support options:
I GOT A LETTER FROM THE IRS
https://ttlc.intuit.com/questions/3605673-i-got-a-letter-or-notice-from-the-irs
I AM BEING AUDITED
If you purchased Audit Defense:
https://ttlc.intuit.com/questions/2924451-i-bought-max-or-audit-defense-and-now-i-m-being-audited
AUDIT SUPPORT
https://support.turbotax.intuit.com/irs-notice/audit-support/
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