Disappearing markup on ipad

Just sat down to mark the student assignments that were done using kami, annotating on a pdf given to them in classroom. When i first open it on ipad pro i can see all the student work. When i tap the pen icon in order to write on it myself everything disappears. Is it not possible to use the apple pencil on top of a kami produced pdf to give feedback to students? If so kami does not work for me!

Could you please share the file with us at support@kamihq.com and mention this post? Thanks!

I have shared the details to Aden but I am still awaiting a reply!

I am having the same issue, if it persists, I see very little use for this extension in my current environment.