March bill insanely high bundle costs

I have been a user of Simyo for some months now and I was overall happy with the service however I have received an invoice above 200€ for last month which is due in some weeks…this really makes me question my decision to keep using Simyo. I have a Simyo complete bundle and I noticed this morning the invoice and the blocking of my sim. My understanding is that this is because I have incurred higher costs due to extra data usage. I have not received any warning or notice about the exceeding of my data usage neither via email nor via phone as claimed in some other responses in this forum. Also the charges per extra data seem not in line with the overall bundle costs of Simyo, this is very unclear and not transparent to users and excessively high (wondering is this is also in line with EU law on roaming). Moreover, the information provided is not complete or exhaustive on the topic in the mobile app. This is insanely expensive and can be a tremendous financial burden for many users including myself. Could someone please assist me to also discuss concession with these costs?