Gross salary diffrnce in pay slip & form 16

Hii experts,
Pls help me to know about GPF.
Actually my friend father is a central govt employee working with CRPF & his total gross earning is 74000 x 12= 888000 approx. In which he contributes 17000x 12 = 204000/- in GPF as per payslip.

But in Form 16 his Gross salary shown 1155000/-.
I want to know why there is a diffrnce in gross salary?

When I asked him about this difference he replied GPF contribution added back to his gross salary. Is it really happens? Why employee GPF contribution added back in gross salary...?

Pls reply
Thanks in advance