Well, you have not said which one of you will claim the children as dependent on your 2021 tax return. If you are not the parent who will claim the child then getting the payments yourself might be a bad idea for you---you could possibly have to pay the credit back when you prepare your 2021 tax return. You can opt out of those payments. If you and your spouse somehow reconcile and get back together and file a joint return you can still get the full child tax credit on your 2021 tax return.
Use this IRS portal to manage payments or unenroll.
https://www.irs.gov/credits-deductions/advance-child-tax-credit-payments-in-2021
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
