Highlighting with apple pen 2. Generation not working

I’ve recently bought an iPad Pro (newest edition) with an apple pen, 2. Generation.

I love working with the adobe reader app to highlight and scribble in PDFs for work, but with the new iPad highlighting doesn’t work anymore. My document is a full text pdf, not an image. The headers I can highlight, but inside the text body, the pen doesn’t react at all. To check, I’ve tried other apps that use highlighting in the same way and there it works fine with the same document. Still, I would love to find a solution for the adobe app, as it is my preferred editing tool.

What could the possible problem be?

Thank you so much!

ps: after further testing, it seems that the only editing tool that is working is the freehand pen.

Message was edited by: Hestia van Roest