I am the owner of 1 shop lot property which I am renting it to my aunt for her small business, I rent to her at 10% lower than the market price. Assuming 6000, I am renting it for 5500 to her.

Recently, there was a realtor who called me up to ask if I am the owner of the property and he told me he can rent it out at higher price than the market value of RM 6000 to RM 8000. And he told me the tenant in my shop now is looking for him to find a cheaper location which means I will have the potential to have no tenant if i don't act fast.

I found it very weird, so I gave my aunt a call she told me no such case. So I went to my shop lot area to dig around, so happened one of the car workshop guy whom I always send my car for maintenance told me their rent increased by 30% suddenly, usually is 7-10% every year depending on rent value. He also suspected the realtor did this because the owner called him and asked him if he is moving out already at the very first conversation.
while there is no evidence we can get this because it is a willing buyer willing seller right, is there any government office we can report these cases to?