Relentlessly trying to add extras which you then have to contact them to undo. Ridiculously poor customer service, waited over an hour to speak to them on one occasion. 3 months to take over from Plusnet. Trying to leave them, post back their router and then receive a revised contract. Hopeless.
To add, same for both home address and my workshop with contract change letter after sending their routers back. Suggested I wanted a new land-line provider and keep their broadband for an extra £3+vat. As if. I wouldn't recommend them to my worst enemy😕