Stop living in your dreamworld. Kashmir was a Muslim majority state, which had been ruled by Hindu kings for generations. And the Hindu king signed the accesssion document. If you google for it, I am sure you will find a copy of that document.
Undivided India was a Hindu majority country. By your ridiculous logic, we should have sent all the Muslims to Saudi Arabia (or some other Muslim country) and kept India for ourselves.
“Azad” Kashmiris do not have a problem with Pakistan because they not “Azad”, they are Pakistanis.