Good day! 

I too have been having the same problem.  In my case, I use the desktop application to connect to QB-Online.  This seems to be a glitch with QB attachments as it does not happen every time but, most of the time.  

• Tried clearing application data & re-signed in - no change
• Tried deleting application and re-installing - no change

I will try logging into through browser and attaching to see if the results are the same...