Yonex Poly Tour Strike moves a lot since the first shot


New User

I've bought a new Prince Tour 100 racquet in October and chose a 1.30 mm Prince Diablo string with it, strung at 24/23 kg. The strings never moved but had notches on it after a couple of months. Since there are no Prince Diablo strings available anywhere in my country I've chosen another string: Poly Tour Strike. They gave me a 1.20 mm version. I've asked for a 24/23 kg tension again.

Ever since I've started hitting with the PTS in January, they constantly move. Now half of the mains are bent. They moved even the first time I played with them.

Is this an issue? Could this be due to its thickness? Should I try a PTS 1.30 mm or choose another string?