I have noticed some difficulties with approving user requests to my apps. Firstly, the Honeycode iOS app doesn't show the notification unless you kill and restart the app. Secondly, even after I had managed to approve a request in Chrome, an erroneous request from the same user later appeared and wouldn't clear as per the image below.
Hi @TPN2000 
We took a look at your issue report regarding this; It's possible that you may no longer be the owner of the workbook or changed roles from the owner. (If you changed roles from the owner, it may result in an error if you attempt to approve access for a user to that workbook).
I'm also raising your first issue regarding notifications not appearing in iOS app for our team to take a look.
Let us know if that helps. If you continue to experience these issues, please feel free to submit another issue report, and we'll take a look into what may be going on. 