The landlord is asking for a rent increase exceeding RERA rental index. What to do?

Dear sir/madam,

My landlord is asking for a rent increase exceeding RERA rental index guidance, and less than 90 days from the end of the existing lease.

I have stated that renewal should take place at existing rent and existing terms since renewal notice was not sent at least 90 days before the end of the current term, however, I have agreed to increase the rent as per the RERA index in good faith.

However, the landlord's agent is stating that the landlord can pull out a valuation from RERA and get a 20% increase (instead of 10% as currently asked, and 5% as per the RERA Index).

What are my options?