I'm in the same boat. My son is an adult, and in 2019 I didn't claim him as a dependent because 1. He is a adult, 2. he made more than $4,000 3. He wasn't a full-time student. This year filing 2020, I claimed him as a dependant, 1. He was a full-time student 2. I provided more than 50%. 3. He only less than $4,000 for that year. I did not file my taxes until the beginning of May since the deadline was extended to May 17. In March my son received a $1400 and in March I received my $1400 plus my other dependants not including my son. Once I filed, I received an additional $1400. My assumption is that they went off my son and mine 2019 taxes and that's why we got our Third Stimulus Check because they didn't have my 2020 yet. Now that I claimed him for 2020 as a dependent they sent me a $1400 stimulus check, even though one was already received by my son in March. Since they sent it to me through direct deposit it been cashed. Is this an Extra, and I need to wirte an IRS a check for $1400? if not, is there any IRS documentation stating this?
Thank You
