Error message disappeared again (Electronic system error)

Hello, today I had the attached error message (see picture) in combination with a warning sound when starting the engine. On the way home I stopped the vehicle again and started again, the same again. The vehicle has already suggested the next workshops as destination in the Navi. The vehicle has only been registered since November and 2500km driven. I then went to the Opel workshop and the error message was just gone again… the workshop could not do anything today. I was told that if no more errors are shown, I can continue to drive and only if the error comes back in the meantime to another Opel dealer in the workshop. The error message might have come due to some humidity or something, which is why it is just gone again… did the vehicle start again tonight, no error message. Do I have to worry about it? Did I have to read it and also because of the electrician’s vacation at the earliest next week? Do you ever have such an experience with such an error message?