Molbile internet on KPN Prepaid stopped working even after top-up

Greetings,

Today, here in Amsterdam, my mobile internet, from prepaid plan, just stopped to work.

Just for knowledge, I saw there’s no saldo anymore, and then I top-up with 10 euro for more 2GB. 

After the payment was proccessed (via Wise), approved by the Wise app, in the browser, it led me to an 500 error page. And then, still no saldo.

I tried once more on my laptop, and the error persists. My phone still do not has internet and I spent 20 euro on this.

How can we procceed?

Thanks in advance

Bruno