The DVLA is no longer accepting D4 medical reports from Doctors on Wheels Ltd.
The company, a provider of cheap medicals for PCV and HGV drivers, is under investigation by the DVLA and Trading Standards.
It carries out medicals in modified vans, often in truck stops and laybys, for fees of around £50-60.
Any applications received by the DVLA since 20 June are not being accepted, and a new application will have to be submitted. The DVLA expects these numbers to be very low.
The DVLA will prioritise resubmitted D4 applications as a result of these investigations. However, it cannot reimburse medical fees.