Three bombarded all of their prepaid customers in October 2020 with a great offer, that later showed it was only send via message to scam the customer out of their legacy prepaid contracts. This offer, when accepted didn't even bring a single cent for the customer. It even cost 10 Euro to activate and ended in November, so that the benefit could never be used ( the offer was send end of October). In addition due to this change, you lost the option, that the 20 Euro prepaid cost is added as usable credit. When you finally find this out, they just say, that's your fault you changed the contract and can't move back. For me this starts with false advertisement and was only used to scam long standing customers out of their legacy prepaid contract. Which is unacceptable in normal years but is the lowest of moral shown in a time of pandemic and need for communication due to lock down.
