Re: Unexpected content from server (got JSON)
Similar issue had been reported a few weeks ago and I thought it was fixed.
There has been a post saying by re-installing the game clears the problem
https://answers.ea.com/t5/Plants-vs-Zombies-2/Unexpected-content-from-server/m-p/12646987#M48609
A little warning: Before deleting the game to do a re-install, please make sure you note down your player ID and if you have not registered your email to get 100 free gems, this is also the time to do so as it provides and an easy recovery method.