Hello @Chaiyapon Singsiri ,
Thanks for reaching out to Microsoft Q & A.
Can you try parted with flag -l
One more thing which I observed was , you were trying to attach the data disk directly to VMSS instance ?
I think, that's the not the best practice. If you directly attach a data disk to VMSS instance - after reboot the disk gets wiped off. Instead add the data disk at VMSS level (Not instance level)
Kindly let us know if that helps.
Please make sure to UpVote and accept the answer where ever it helps out in the resolution.