Reports of tradesmen cold-calling local businesses offering to paint their car parks have sparked a warning from the Office of Fair Trading.
The tradesmen claim to be subcontractors at the Department of Infrastructure and offer to do the work with leftover materials.
But the DOI says its employees don't carry out this sort of work and those claiming they have the department's blessing could be prosecuted.
If you have any concerns, you can contact the Office of Fair Trading on 686500.
Want to start training to become a nurse?
Appeal launched after fly-tipper filmed dumping rubbish
Prepare your pets for Bonfire Night, says Manx charity
Manx Care bringing in mobile translation machine
Steam Packet says it would get too many Freedom of Information requests
Vintage TT trophies on sale for £5,000
TT merchandise company still owes government over £100k
Manx Care's annual assessment shows £15.6m deficit