Hi Laura, I answer your questions
Do you have the latest version of WordPress ? If not update those. Yes, It does not work
Do you have the latest version of Kleo theme ? If not update those Yes, It does not work
Do you have the latest version of plugins installed ? If not update those Yes, It does not work
If you de-activate all plugins excepting BuddyPress/bbPress it works? if yes enable back plugins one by one to identify what causes this. It does not work
If you de-activate the child theme it works ? It does not work
Let me know
I wait for your news. Thank you