I have only used the HRM PRO PLUS twice and some creases have formed on the elastic band.
I must say that I had only once had a defect like this with a Decathlon heart rate monitor and they had replaced it under warranty. I'm talking about a heart rate monitor for less than 20 euros.
As for the HRM PRO PLUS, I don't know what could have happened, after all I have adjusted it like the other heart rate bands I have worn so far, always washed in the shower after each lap and left to air dry before putting it in place.
In your opinion is it a defect that could worsen over time or is it just the heart rate monitor that takes that deformation and remains constant over time? How should I behave, also given the cost of this accessory which should be the top of the range in its category?