Issues with capacitive pens on Microsoft Surface

I'm running Windows 10 1803 on a Surface Pro 2017 (i5/8GB).
Most of the time I'm taking notes in college using OneNote. That's where I've encountered some weird issues: From time to time (days to weeks) the "ink" just randomly smears over the canvas, even with the tip not touching the display at all. This goes on for a couple of minutes until I decide to rage quit and put my pen away. This has happened with both pens that I use (#1: https://www.amazon.de/gp/product/B07BXQR3TR and #2: https://www.amazon.de/gp/product/B079JX4DVT (which is a Microsoft-certified stylus)). It only happens when the tip has already touched the screen before, not when you approach it after taking away the pen. This issue is apparently not exclusive to OneNote as it affects the whole Windows environment. However, I have not been able to reproduce this. It just happens when it does. No updates beforehand, no other running programs, etc. Some things that I've already tried include changing the pens batteries, cleaning tip and screen and, of course, rebooting.
There's nothing more annoying when you just want to write something down and this messes up your entire page: https://www.youtube.com/watch?v=8bukB_CH_jw

If there's any missing information needed to solve this, tell me. Thanks in Advance!