Question to the Home Office:

To ask the Secretary of State for the Home Department, how many recorded instances of enforcement action against users of mobility vehicles for breaking rules of their use there were in 2020.

The Home Office does not hold the information requested.

The Home Office collect and publish data on use of various police powers, including Fixed Penalty Notices for motoring offences. Data as of March 2020 are available here:
https://www.gov.uk/government/statistics/police-powers-and-procedures-england-and-wales-year-ending-31-march-2020

However, data specifically on enforcement actions against users of mobility vehicles are not available.