why slag Freeborn bikes off on an open forum when they did not sell the bike to you?
take it up with the original retailer you bought the bike from in Spain.
First port of call always resides with the original retailer, not the distributor of the brand of a new country you were not in, when you purchased the bike
this does not just apply to smaller brands like Devinci, even the big brands like Specialized have removed "Global warranty" because distributors for each country build a "cost" of an expected warranty claims into their margins
-did your original retailer in Spain supply the shimmed seatpost?
-or is this something you fitted yourself?
-did you use fibre grip (carbon paste) whilst fitting the seatpost?
-did you use a torque wrench (5nm) on the seatclamp when fitting the seatpost?
I ran my Dixon with a 31.6mm Reverb with zero issues, sold the bike 2 years ago and new owner is still enjoying the ride with zero issues!
something to understand about using a shimmed "dropper post" is that they introduce a stress/strain load to the seat tube that the frame was never designed for
it was designed for native 31.6mm and that is what you should have used, rather than cheaping out and bodging the fitment using a plastic shim to fit a smaller seat post into a larger seat tube