I filed my return already and got a refund i should have got more if my mother or sister didnt claim 3 of my kids how do i get my child tax credit that im entitled to now

[5kidsandus]

How do i get the child tax credit that im entitled to after my mother or my sister already got paid for my child and no right to

[Hal_Al]

You don't say where the kids live. Just because you're the parent doesn't mean you're entitled to claim them.  There is a limit to how much child tax credit (and earned income credit) you can get. It is not a straight $2000 per kid.

The money you hear about people getting for just filing a tax return claiming kids requires them to  have some earned income (wages or self employment). Without earned income, they are not eligible for the "refundable" Earned Income Credit or Additional Child Tax Credit.  Both credits are calculated on the amount of earned income you have. No earned income means no "refund". A small amount of earned income means a small refund. The child tax credit does not "kick in" unless you have at least $2500 of earned income.

A child can be the “qualifying child” dependent of any close relative in the household. If you live with someone else, e.g. your mother and sister, it may actually be better if they claim your child(ren).

[Hal_Al]

If someone else claimed your child inappropriately, and if they file first, your return will be rejected if e-filed. You would then need to file a return on paper, claiming the child as  appropriate, or, in your case, file an amended return. The IRS will process your return and send you your refund, in the normal time. Shortly (up to a year) thereafter, you'll receive a letter from the IRS, stating that your child was claimed on another return. It will tell you that if you made a mistake to file an amended return and if you didn't make a mistake to do nothing. The other party will get the same letter you did. If one of you doesn't file an amended return, unclaiming the child, the next letter, from the IRS, will require you to provide proof. Be sure to reply in a timely manner.

Winner gets the tax benefits; loser gets to pay the IRS back with penalties and interest.    

https://www.thebalance.com/claiming-same-dependent-audit-risk-3193030 

[SweetieJean]

Amend and file it by mail. The IRS will investigate.

https://ttlc.intuit.com/questions/4518552-how-do-i-amend-my-2018-tax-return

Also see:

https://www.irs.gov/individuals/how-do-you-report-suspected-tax-fraud-activity