Dear khun Esa,
Let me interfere to explain about the notice.
As you are holding the property under company name
By Thai law clasified the objective of holding likes for business use, so the local government has the right to call for paying TAX
In case of hold by personal name, the government also call for tax if you hold over one house.
The exception is for the 1st house only as they will clasified likes a house for living.
Actually this matter must assist by accountant whose works for financial annual audit report which all the company registed in Thailand should submit to Revernue Department.
Can you please advise who is response as accountant or lawyer whose proved your company, so we can contact them to hold this case?