Form for PF wages restricting to 15000 by the employee.

Employer deducting the Pf on actual PF wages of the employee and providing the equal contribution. But Employee requesting to restrict the PF wages to 15000 for PF contribution. Will there be any form to be filled

The law requires the company to deduct and pay PF upto a salary ceiling of ₹ 15,000 per month.
It does not prevent higher contribution but the same must be by consent of the worker.

If the employee no longer wants to contribute more, a simple letter as request is enough, there is no specified form.
However, if the PF scheme itself is that it will be on full salary (which often happens with companies having their own PF Fund), the option to reduce the same may not be available. You need to verify that same.