Capitec sms

I just received an sms from capitec Bank saying I should email them a proof of income and address but they did not specify what kind of proof they want, because I sell wigs so should i ask all my clients to give me the proof that I supply them with wigs or what. And I hope you're not going to block my account with because the money that's in my account does belong to me it belongs to my clients. Please specify what kind of proof do you want and we use bank statements as our proof of address. Maybe is time to use another bank if you going to give me run around with the money we work so hard for