you don't need to provide a departure date or details on the TDAC it's not a mandatory field. On the other hand though, on the old paper format you had to provide all that, departure date, accommodation details, flight numbers etc etc.
I have a kbank account and when you go into a branch they will attempt to set it up but it will be flagged by the system and state it can't be activated when trying to increase limit above 50k, the only way to transfer more than 50k right now is to call and have them temporarily increace the limit for a few hours.
if all else fails and you're 100% certain your documents and information were correct jist go and apply from another embassy. Taipei are quite quick with issuing
when a number becomes inactive they disable it for X amount of time and then its reintroduce into the pool of available numbers after that X amount of time of it being out of service.