Lots of TokenMismatchException in logs (all from android devices)

Hi guys I'm kinda lost

I see A LOT of TokenMismatchException exceptions in my production logs and all of them came from android devices (Iog the useragent, ip, url and request method with every exception)

It's basically a simple landing page with form so I see no reason people might be on page for few hours (that'll cause session expiration). I also pass the XSEF-TOKEN cookie content using the X-XSRF-TOKEN header so this is not the problem

I tried using my iPhone and everything worked with: Safari (both private and regular modes), Chrome and Facebook inline browser

I also tried using my girlfriend's LG G4 using Chrome, Built in android browser and Facebook inline browser and it worked as well.

I temporarily disabled the csrf middleware for this specific route so people won't get errors but this can be really bad. So what should I do next?

I'm using Laravel 5.2, sessions driver is file (cannot do redis from the server the client gave me) and the sessions directory is writable. Lots of sessions are in the directory so this is not a permissions problem. PHP version is 5.6.18