@Feujarau57
I think it is not possible to do an upgrade from Rel. 8.x directly to Rel. 11.x.
You can try a factory reset of the box, but even then there is a certain risk that the box will no longer start.
I therefore recommend that you contact support and, if necessary, request 2nd level support, as the problem is rather unusual for 1st level support.
Phone 0800 800 800
or
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