Uval,
Thanks for you reply. I tested yr site and I cannot upload. I am using the native browser of a Xiaomi phone. I then downloaded the Chrome app on the same phone and it did work fine, except I still could not submit (but i did submit in your site which makes me think i have something wrong in my form submit button).
Also, my friend had same problem for loading and submittig on Samsung S6 with it’s native browser.
I hope this will help.