In response to your query,
In 2013, the government released a new circular stating that PAN details had to be mentioned for HRA exemptions for amounts above Rs. 1,00,000. The government reduced the figure from Rs. 1,80,000 so that employees could not file HRA exemptions without their landlord’s PAN details.
The government has found that a number of individuals who lease properties and collect rent do not pay tax or declare this income in their tax return. As a way to ensure that individuals declare this income, the government has made it mandatory for renters to include the PAN details of the landlord in exemption claim form, so they can check if the landlord is declaring the rent as income when filing tax returns.
This maybe the reason behind non cooperation of your landlord, in this case you can file a formal complaint against your landlord if you are under a rental agreement to use the property for certain amount of time or if you are not under any such agreement I suggest you to just leave the property and look for a different property for your use.