When users try to reply on a thread on their mobile it very often happens that they just bumps to first post in thread without submit the post. I have experienced this myself. I then go back, and send again. Sometimes it takes 2,3 or 4 times before posting is successful.

I use wordpress 4.5.3
bbpress 2.5.9

Is there any tip on how to find the error?

I use this theme on mobile:
GM Neo (Graphene)

This app to mobile switch:
Any Mobile Theme Switcher

I also have the following plugins for my bbpress:
GD bbPress Tools
bbPress Go To First Unread Post
bbPress Unread Posts v2

[@robin-w Moderator 8 years, 5 months ago]

bbPress is tested with wordpress default themes. It maybe a conflict – you need to check plugins and themes

It could be a theme or plugin issue

Plugins

Deactivate all but bbpress and see if this fixes. if it does, re-enable one at a time to see which is causing the error.

Themes

If plugins don’t pinpoint the problem, as a test switch to a default theme such as twentyfifteen, and see if this fixes.

[@robkk Moderator 8 years, 5 months ago]

Contact your mobile theme author to see what possibly could be the issue.

[@trehesten Participant 8 years, 5 months ago]

Deactiveted plugins, didnt help. I have sent a support request to theme author. Waiting for reply. Will follow up here