He6n corridors sometimes don’t go in

Servus, I have a problem with my Er6n, which I have been driving for a good 3 weeks now. It often happens now that 3, 4 or 5 gears don’t go in immediately. I speed up, whether strong or leisurely makes no difference, and when I turn up I pull the gear lever up but the previous gear stays in it. This happens at least once per ride. Meanwhile I am so sensitive that I notice when the quiet “crack” is missing and the gear is not in it. I have a in a few times with not very little gas in the previous gear. If the problem occurs I can pull the lever up to the stop without the gear going in. then I let it go without coupling it in and then it works for the second time mostly. Does someone have similar problems? Can’t it be that on an 8 years/23000 km old motorcycle the gear is already hackier than on a Samson from the 70s. Umfaller had it according to the previous owner and after I’m still a driver. Do I pull the lever up too fast or too slowly? That’s why I didn’t notice it during the test drive. And that was quite extensive with 50km. I only have the problem for about a week. I’d be very happy about tips and hints, so I’d miss the pleasure with my new mope. I’d like to get some tips and hints. d. LG wePsi