The version I'm currently on is 11.4.1...
It's getting ridiculous now...
What device (make and model) are you using?
This problem has been reported when players running an out-of-date version but after updated with a latest release (currently 11.4.1) things should be back to normal. Your problem seems to be unique and if you have not noted down your player ID and registered your email address to link to your account (game saved progress) I recommend you do this now before making any further attempts on re-installation.
I have a Motorola Moto G(60).
I also think the problem started before other players flagged it...
Everthing else works fine on my phone.
How can I do a reinstal without losing all my plants?
I have a check on the G60 spec and it should be supported.
To be able to re-install the game (or do as a new installation on another device) without losing progress, the easiest way is to register your email address with PVZ2 by clicking the cloud button (at the bottom left corner) from the main menu. You will also receive some free gems if the email is used the first time. Once this is done your PVZ2 account's progress is linked to your email and ready to be used again on re-installation.
