You could call the company with questions.
Going to a flatter shoe is a progression based on what you are currently wearing.
It may take 1 or 2 pairs before you are at a shoe with zero difference.
Transitioning to a flatter shoes asks alot more out of ankle rom and heel cord rom.
Working with ankle rom, heel cord, calves is an important aspect so your body doesn’t make other compensations when looking for stability or slack within the system.
Daniel if you have been working on ankle rom and are not seeing improvements you aren’t hitting the aspect that is causing your restriction.