Urgent request: Dispute unexpected €100 charge and blocked SIM card

Dear Simyo Customer Service,
I am writing to dispute an unexpected charge of around €105.48 on my account and to request that my SIM card be unblocked immediately.
I do not accept this charge because I did not knowingly use mobile data in a way that could justify this cost.
On the day this happened:
 1. I was at home with full Wi-Fi coverage the whole time.

2. During that time, I was in a meeting with my colleague on my laptop from 5:30 PM to 7:12 PM, and I did not use my phone at all. My laptop was also not connected to my phone hotspot. However, according to the usage record, mobile data was used from 17:56, which was during my meeting. This makes the charge impossible to understand, because I was not using my phone and was not sharing internet to my laptop at that time. I can provide evidence that I was in the meeting through my laptop.

3. When I received a warning that my data bundle was finished, I immediately bought an extra 500 MB bundle specifically to prevent extra charges until the new billing cycle.

I did this because I am aware that these costs can happen, and I wanted to avoid exactly this situation.Therefore, it is very surprising and unacceptable that I was still charged around €105.48, especially while I was at home, connected to Wi-Fi, and away from my phone.                       I have been a loyal Simyo customer for years. My usage history should also show that this is not my normal usage pattern, and that I am careful with these kinds of costs.

I kindly but firmly request that Simyo:
Unblock my SIM card immediately. Removes or corrects the unexpected surcharge from my bill. Provides a clear explanation of how this charge happened.

Please treat this matter urgently, as I need my SIM card to be active.

Kind regards,
Kuntida Narongwattana