Service Charge

Maintenance

We have a couple of flats as part of our portfolio for which we pay a monthly service charge to Property Mangement Companies. One of the Management Companies for one of the flats is being very elusive, is not responding to emails and is not arranging for neccessary cleaning/maintenance of communal areas. We have threatened to stop our monthly payments to them until such work is carried out - that did get us a response, but only to inform us that if we stopped our payments this would breach the terms of our lease. The company is not local to us and  presumably does not visit the block of flats, despite our emails informing them of work that needs doing. Does anyone have experience of resolving such an issue? At the moment we feel like they are pocketing our £800+ a year and doing nothing in return.