Sam Khan Visa is expected to be the actual permission to enter a country. If this is the case, it is good impression for a country to correct a faulty procedure.

Sam Khan So unfair!

Means "it is not valid." They have probably found a record against you shortly after they have issued the visa.

No, you aren't.

1. How many days will your first stay under the visa required last? If you are not sure, write an approximate count of days. 2. If not yet decided, write it, although it is better to have a hotel in mind to reserve, and write its address. 3. Your employer or source of revenue that guarantees you will have enough money during your say. 4. Someone like No. 3 inside Thailand. You can simply write "None" if there is no such a person or entity. Good luck! Give my best wishes to beautiful Bangkok!