Last year I had to file with my ex per our divorce agreement. When we got the stimulus payments, we split them 50/50. How do I claim that now that I am filing single?

[AlanT222]

If your stimulus payments were based on a joint return, you and your spouse are each treated as having received half the payments that were issued. 

So enter half of the payment you and your spouse received.  

[fanfare]

Since you already got your stimulus payment, there's nothing to do on your 2020 tax return.

EXCEPT,

TurboTax starts off assuming you did not get it.

So therefore enter that you did get it.