I too am having serious difficulties with Bitmine CH.
Briefly, I previously had a 'hosted' contract with Bitmine CH (delivered late), running rigs with 1.5 Th/s at their facility in Switzerland. However, this was abruptly terminated after just 4 months when, it seems, the power company simply pulled the plug on their facility because they couldn't pay their power bill!
I had already started a cloud mining contract with them (also delivered very late), supposedly running 10 Th/s of hashing power, but so far there is no way that its performance corresponds to 10 Th/s. They made a vague offer of more hashing power on this contract to compensate me for my losses on the 'hosted' contract (purchase of rigs, premature closure of contract), but have not 'delivered' on this either, and simply refuse to answer any of my emails
I feel that a possible course of action would be for a bunch of us to show up on their doorstep, and maybe go and see the local public prosecutor in person, as well as talking to a local newspaper perhaps. An air ticket to Switzerland is a cheaper option than legal action!
Anyone interested should email me at:
edit.rfr@gmail.com Mark