Seems the rate at which you can use contactless payments is to rise from 01/04/2020 to £45 in an effort to reduce cash payments.
I am doing shopping and picking up prescriptions for people and of course they have to pay me in cash as like most people I don't have a machine.
Don't forget to check with your insurance company before using your car to run errands. Had to change my insurer to get cover and cost me considerably more.