Hello Red----and welcome. Sorry we have to meet this way!
OK - if this scooter is still under its fully transferable 24 month warranty from when first registered for the road - You need to take it back to the Kymco dealer!
Will it start, now? Will it idle, now?
3 blinks does indeed point to the TPS (throttle position sensor) But, as noted, a failing TPS has never shut off a LIKE engine, or stranded the rider!
OK, simple things first, is the red Kill switch in the RUN position???
Any quick history with this scooter will be helpful - miles?, crashes?, other problems recently?, recently serviced by anyone? - ie. has engine, battery, etc. been touched by anyone recently?
One possible fix - "turn key on and wait for at least 5 seconds, do not start the engine, then key off - do this at least 3 or 4 times - waiting 5 seconds before switching off."
Any good?
Waiting for your responses to the questions.
Stig