Calendar completely messed up

Hi
since the last update of your plugin our calendar is completey foobared

1: It was a list before – not a month view
2: it cant be changed into a listview anymore
3: if you click on the link that leads to the last month there is no link that leads you back to the actual month
and a lot more strange issues

And by the way – its not the first time we had problems with it.
To be true – there havent been a single update that went without without problems.

How to fix the actual desaster, please?
Danny

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