Unlimited home internet for an effective €8.87/month – Am I missing something?

Hello everyone, I've thought of a little tariff trick to drastically reduce the fixed costs for home internet. Since every euro is optimized here in the sub, I wanted to share my plan with you and ask if I have a mistake in my thinking somewhere. ​ ​ The invoice (for 24 months) I plan to take out an o2 Unlimited Max contract (100 Mbit/s 5G) as a bundle with a smartphone and liquidate the hardware directly. Total contract costs: €826.80 (includes o2 Unlim