Just got a £100 fine from Dvla for my van for no insurance on it even though its in a Garage awaiting Repair

its taxed but laid up with a blown engine as that's way it was when I bought it 4 month ago

I haven't insured yet it as I am waiting for it to be fixed first

do I need to pay this fine even though its at a garage + inside awaiting repair?

can I appeal against this or do I need to pay this silly fine