Pest Control do not offer treatment for bees. The reason they don't treat bees is because they're not a pest. Pest Control class bees as beneficial insects. Whilst they may be closely related to the wasp, most bees aren’t aggressive and usually won’t sting humans, and they're also one of the world's most important pollinators.
If you can identify the bees as honey bees, we recommend that you contact the British Bee Keeper Association in the first instance as they may be able to remove the nest.
For other species of bees we recommend you call a private pest control firm.