I think you might have a case for harassment if they are coming to your house on your day off. You'd have to check with your local laws to know for sure.

I'd try to diplomatically explain to your employer your desire to be left alone on your time off, as bringing an outside agency into it might bring your employment with this company to end. (Probably not directly, but a company that wants to get rid of an employee will find a way.)

My personal opinion is that it's a bunch of crap for them to come to your house when they can't reach you by phone.

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In memory of my friend skip...
Go then, there are other worlds than these