The following wording from, Federal Foreign Office Germany:
Travel to the provinces of Narathiwat, Yala and Pattani and parts of Songkhla in southern Thailand is strongly discouraged. Please note the worldwide safety notice. "Terrorism

The global threat of terrorist attacks and kidnappings remains unchanged. Even in Thailand, attacks cannot be ruled out, even in vacation areas. Most recently, there were minor bomb explosions at various locations in Bangkok on August 2, 2019.

In the provinces of Narathiwat, Yala and Pattani and parts of Songkhla in southern Thailand on the border with Malaysia, there are regular clashes between separatist groups and security forces, as well as terrorist attacks, including on targets frequented by foreigners. Emergency laws apply there. In individual districts, especially on the border with Malaysia, curfews can be imposed at short notice.

Be especially careful in busy places and on special occasions.
Always follow the instructions of security forces, in the event of unavoidable stays in the southern provinces even in the case of night curfews.
Observe the worldwide safety notice. " Please note the worldwide safety notice.