I have joint custody and the other parent won't let me see my kids what can I do I don't have money for an attorney

Has the court ordered a visitation schedule? If not, then you go back to court and apply for visitation.

Really not enough info, what type of Joint custody, legal or physcial. Is there a court order on what days, or what weeks you are suppose to have the child.

When did they stop allowing you to have the child during your time. Also if you have "joing" custody you are not seeing the child, you are getting the child for your time, normally split fairly equal between the two parents.

If she is breaking the court order you will need to take her back to court. In the US often there is a legal aid department that can help in each county