frozen septic line.. need plumber or septic person?

[Wingham]

I returned from MI and my septic pipes are frozen or clogged.  Had a neighbor take a look, and not sure if frozen in the crawl space or outside.  I have called a couple of plumbers (ned area) and they don't come to Bar K.  Any suggestions on who would come to assist with clog/ frozen pipes?  I have had the low areas ( laundry drain and downstairs toilet ) back up onto the floor, then recede.  tried running hot water and can for some minutes, but then still clogged and back up in same areas.  So looking for name of company person and not sure if it needs to be plumber or septic person?  thank you for input.  Happy New Year!