Angela Jones, 60, popped into town to collect some photographs and pulled into Kings Heath High Street car park in Birmingham.
One of the ticket machines was broken and a sign said she needed to scan a QR code in order to pay on her phone.
Angela says she tried downloading the app but became suspicious it was a scam so deleted it from her phone and left the car park on October 31.
A week later she received a £100 fine from Parking Charge Collections Ltd (PCC), saying she had exceeded the five-minute limit by 65 seconds.