Kinda jp question but also applies to global

So last night I was starting up jp and was rerolling to try and start with the anniversary unit right out of Fuyuki. I do a few rolls, uninstalling in my apps and then reinstalling in apk to reset my save data. I go to sleep because it's late, and when I wake up I suddenly find that uninstalling no longer erases my save data? Is there any way to change that or did I give the account too much time to cement in the servers or something?