Apple pencil, switching to eraser not working.
hi, I have been using Apple Pencil with Acrobat Reader on my iPad Pro 2018, and I just found that I no longer can switch to eraser by double-tapping the pencil, which means I cannot erase things I wrote on the pdf files. I am pretty sure I could do it before, so I am wondering if you could help with solving this issue. FYI, the double-tapping function works perfectly with other apps, so I presume it's not because of the malfunction of the pencil itself.
