Appaulling service

Cancelled my landline 28th aug giving 1 months notice as required. Now 21st of Oct and they still havent given me my R700 deposit back even though there is nothing outstanding. Quick to take money from you but when they have to pay it back its differnt storey. Why should i have to wait a month for my money back. It should have been given back to me the day my account closed should have been 28th sept. Everytime i phone they are so unhelpfull and just escalate it . Saying i have to put in a dispute to get it back ? Bunch of ******* holding on to my money claiming interest off it all this time