Engagement is everything. You need them to own the customer service programme.
Training is not the issue. Do they really need to be told to smile when they answer the phone?
How would you like someone giving you a few hours of tips and some role-plays on how to treat customers well?
Your colleagues know all that stuff too. They may not always do it, but they know it, because they are customers of doctors, hairdressers and other people in your organisation.
Respect your employees' knowledge and draw on it
It's about asking, not telling. If you tell them, very little will change and when you try to revive your customer service programme, they'll be even more cynical about it than they are now.
If you genuinely consult them as the experts on customers' experiences and needs, then ask them to come up with their own ideas, they will own the programme.
Ask them, 'What's it really like being a customer of ours?' (You might not like what you hear, but welcome it.)
Get them to think of specific issues: what customers see when they walk in, what happens when everyone is busy or out and whether everyone really does go the extra mile.
Watch how even the office grouch suddenly gets interested when you consult, face reality, then help them turn their ideas into action.
Help them develop simple customer service projects and set up a progress board with target dates and names to show who has chosen to be responsible for each project. We've had teams competing to finish more customer projects and accusing the other teams of just taking on the easy projects.