I am a new to FXTH8700,i meet a problem that is in debug mode is ok,but flash can not run! or re_power also can not work!
I would recommend you taking a closer look at the attached document describing all the necessary steps for programming the FXTH87xx devices.
There is also a similar thread discussing this topic - e: FXTH870502DT1 programming
PS: If my answer helps to solve your question, please mark it as "Correct". Thank you.