The rights of a father upon divorce

I have given divorce to my wife on 3 multiple occasions as per her wish to force me to give her divorce verbally, then she came to Dubai on a visit visa along with my kid.

She has requested me to sponsor her with a wife visa just for few months. She has convinced me and I sponsored her with my kid.

Now for 2 years, I am telling her to cancel the visa as she promised but instead, she is blackmailing me. During these 2 years, I took all my child's expenses. She is trying to get the child's full custody and she will not allow me to meet my child.

Even now she blocks all my contact and shifts her house to another area.

Kindly advise!