I read this as you having to contact them in order for them to credit you for overcharging you for a retired product when the replacement equivalent was priced lower.

Why didn't they proactively inform you that your service was retired and there was an alternative available?

It sounds like this must have been going on for a while to be worth 6 months of service in difference alone.

I left 1and1 close on 2 decades ago. If you consider this a story of good service, then I would suggest you try some other provider.