Budget Car Rental Sent us a rip-off letter a year after we rented saying we left spills, stains, liquids in car $450 fee which was a LIE Detroit Michigan

We rented a 4runner from Budget.  We took care of the car as we always do.  We turned the car in, no damage, got our final bill emailed, which was correct.  We never even had so much as a soda in that car!  We didn't take it off road, no mud, or anything. 

We rented the car for a funeral.  Then, almost a year later, we get a letter from "Nora Henry" saying we owe $450 in damages for soilage, stains, spills.  Which is a LIE.  This is very upsetting and infuriating.  This is a rip off SCAM by Budget.  I've tried calling twice so far, to no avail.  Will try calling again tomorrow.