I’m facing challenges with detecting Aruco markers (I am using DICT_5X5_100) , even when the image contains only the Aruco marker and no other elements, detection consistently fails.

I am using a 6×6 aruco marker in the form of a sticker to track vertical jump characteristics of an athlete. My main problem is the conistency of data.
It seems to be near perfect in some videos, with >90% detection and accuracy to within 1cm of the actual jump height determined by forceplates, but others <70% and unusable data. The video is shot on 240fps using iphone cameras.