bad service

We bought Trimrech electric lawnmower and went to return it because the house runs on a single phase power supply and the machine is not suitable for the house and all the electrical plugs trips the electricity on the main switch. we therefore wanted to be refunded for the machine, they refused to refund to give us a refund, they said they will send it for assessment, in my view this whole process is useless coz the machine works but not suitable for our house, we need our money back, we don't want the machine. they said they only refund if you bring it back within 14 days, but how often does one cut grass? it not something that you do daily, so obviously the 14 days has passed and we want our money back. we can't keep something that we cant use. Assessment note: ***, TRIMTECH 2200W ELECTRIC LAWNMOWER