Rename shared calendar

I have persons at my job who have shared their calendars with me but they are all named calendar. So i would like to rename them in Em client.
I have rename them but it doesn’t work.

Generally the name is provided by the server, and unless you are the owner of the calendar, you can’t change it. So you might rename it in eM Client if the option is there, then after a while it reverts to the server name.