I have a problem with the health insurance company that issued the policy I am required to have for my long stay (OX) visa . Because I am over 65, they required me to have a very comprehensive checkup/report that cost several thousand Baht (and then listed a dozen or so conditions they will not cover, with no price reduction). They stated clearly (in an email) that a defined portion of the checkup/report costs would be refunded to me if the cover went ahead, but after a couple months they claim to have made a mistake and will not make the defined refund.

Is it possible to pursue the company for the promised ~ 5,000b ?