A UK Visa refusal is so easy to get
A visa to the UK can be refused for all sorts of reasons including lack of documentation, presentation, and your Thai partner saying the incorrect thing or supplying the wrong Thai documents which is very common and seen daily, a UK Visa application can be like a mine field and full of reasons to be refused including not enough proof of the relationship, finances not sufficient, not a good enough reason to return to Thailand after the visa has been awarded which is why you need help to prepare , present and do the application properly and using Key Visa will get you the result you require as a refusal is heart breaking and makes it so difficult in a repeat application.