Being Harassed by Call Centre Agents

These people will call you every minute. Literally every minute, happened to me today. They will harass you. The call centre agent Kamogelo even told me that i will keep on getting calls from their more than 200 staff if i don't give them a payment date, even though i said that i do not know when i will have the money to pay. They want me to give them a date whereas i do not know when i will have the money... Am i supposed to rob the bank or what? I will pay when i can, haibo!