I am pretty successful in initiating the talking and then leading to the dancing/grdining stage with girls in the club. However I am not able to get the girls number or get them to stay for longer can anyone help me understand what it could be.

Generally I say hi and have the usual small talk while dancing with them. After some time i ask to buy them a drink and later when the girl says I need to go or something I ask for her number, sometimes I get the instagram and sometimes I get the number but almost every time they dont respond to my text.