The transfer of my number was completed this morning. 

Because of the transfer, the statistics of the old SIM were mixed with the new one in the iPhone settings. I decided to delete the eSIM and request a new one to fix that.

The first problem was that in order to request a new eSIM I had to get a text message (which was impossible as I had deleted the old one). I chose to verify with my bank account. This is how I got the eSIM. But in the phone after that it was "not serviced". 

I tried a few more times to delete and request eSIM, but the network still did not work.

After that, I texted simyo on WhatsApp but got no response.

At some point everything broke down altogether and I got "We konden SIM niet downloaden en installeren. Probeer het opnieuw."

Now I can't request a new eSIM because I can't get the code and the confirmation through the bank shows an endless progress bar.