PSU office doesn't want to pay rent at market price.

We have rented our building with PSU offices(total four offices) . All the offices are tenant since 20-25years having lease deed of 10 year duration and option of 5+5 with 20% increment in rent. One of the lessee didn't want to give market rate rent. Their lease agreement had expired 3 year back, and they want to make new agreement with 100% increment in rent. But, the market rate is equal to 300% of the premises old rent. All the other three offices are paying market rate and had also increased the rent above 300% to give market price at the time of agreement renewal. We make it happen by submitting proof of rent of other offices beside our building and locality. But one of the lessee doesn't want to give market rate of rent after submitting all the proof of current market rate. So, we have planned to vacate the premises and already given 3 month notice, but we are not getting any response of our notice. And we are now planning to go legal to evacuate the PSU office from the premises or to get the rent at market rate. Do legal evacuation process will take long time? Do the lessee will force to pay market rate (i,e.,300% increment in rent), if they are not willing to vacate the premises? If they vacate the premises, what rent they will pay on vacation of premises. As 3 years had passed away since agreement expired.