Toyota C-HR Hybrid starter battery problems?

Hello everyone, maybe someone can help me here.

I have owned a Toyota C-HR Hybrid since July 2020, which I bought new back then.

A good car in itself, but unfortunately there are now increasing problems with the starter battery.

The first time about 3 years ago after a downtime of more than 2 weeks.

Twice last month: on September 2nd after it had been standing for about 2 weeks and on September 25th after 5 days, I was able to start the car for the first time, but then when I turned the car off after a short drive of about 1 kilometer, it wouldn't start again.

In both cases, I contacted the Yellow Angels, then drove 20 km and the car worked as usual.

After the second breakdown, I went to Toyota, and they said the battery was fine. However, since it was a short appointment and they didn't take long, I assume they only measured the voltage.

Is there anyone here who has had similar problems?

What is your opinion on how long the starter battery should be able to bridge?

I suspect the fault lies more in the wiring or a consumer that isn't shutting down properly. Can such errors be read via the onboard computer or monitored while the car is turned off to see if power is flowing anywhere?

I also remember that after I bought the car, the horn didn't work. The seller fixed the problem. Later, as described above, the battery issue first appeared. Could that be the cause of the problem?

thanks in advance