My calendar deletes past events?

I have the huawei p10lite and use the existing calendar app.

Now I have things which I weekly so synonymous stored. (Repeats on Tuesdays, or repeats Monday through Thursday…)

Now I usually enter additional appointments such as a celebration, working hours or a doctor's appointment.

it is now so that exactly these additional entries are always deleted (believe monthly). For example, all my appointments from the past few months (except those that repeat themselves) have disappeared.

However, it is sometimes useful to know what you were at the doctor's last week or something.

That's why I would like to know, how can I prevent the delete and how can I get my old appointments again?

Hm,
can't help directly. Have Honor9, which is pretty similar. Second brand of Huawei, a little less expensive and a little less "top", but I do.

Because of calendars:
From (bad) experience I never rely on computer calendars, synchronizations, clouds, NAS or anything like that. Although I have such. But I fell on it too often.

It may seem old-fashioned and probably it is:
Every year I have paper pocket calendars. And notepad. And of course pencil and eraser. Only fools or optimists write in their calendars with pens…

When I was still working, I put a big calendar open on my next table, with all my business appointments. Of course not my private stuff. Pen next to it (not pencil). When I left, my office was locked. Only my wife and my secretary had keys.

These are ancient methods. Is somehow failsafe. Not quite, but a little better than computer science.

Hmm Well, eig was happy to keep the app because I like everything else really great… Just that it clears my data is really stupid.

Also have an "old-fashioned calendar" but my phone is just better and faster to place and ask if I need the calendar.