OneDrive Mobile App

Good Day

We heard today an interesting case where a user is having problems in editing files hosted in OneDrive through mobile devices.  For example when using the OneDrive to open a PDF file and looking to make annotations, the user does not see the standard controls on the app such as the pencil (to trigger the annotation or the search magnifying glass or the other controls we normally see.  Looks an isolated behavior just to one person either on a tablet or mobile phone. The OneDrive account is in good shape with no storage restrictions or permissions issues. Things work well when leveraging a desktop/laptop when working with OneDrive files.  Posting this in case someone had came across a case like this. Thanks