One problem could be if your return got checked for spouse is a dependent. Turbo Tax is investigating this issue, sign up here
https://ttlc.intuit.com/community/tax-topics/help/spouse-claimed-as-a-dependent-box-checked-on-2019-...
Can you check your 2018 returns and see if that was checked back then too? We are seeing reports it was. So that may have started in 2017 or 2018 and transferred to 2019. Probably never would have been a problem and caught except now because of the Stimulus Check.
You will I'll be able to reconcile it on next year's 2020 return and get the missing amount.
