Why I only got 1,700 on stimulus check if I have two kids

Was maybe one of your kids 17 or older in 2019? You only get the $500 if your child was 16 or younger at the end of 2019.

I wanted to no how do I no if my stimulus  chk is pending are not

Yes he will be 16 in December.

You can check the status of your payment through the IRS Get my Payment site.

Do you always claim both children each tax year? Were they both under 17 in 2019? 

Yes I claim both and they are under age on was born 2004 the other one in 2006

There have been a number of people who have not gotten the extra portion for dependents. The IRS has not issued any information on this. They may be verifying dependents.