Can't increase my overdraft

I Spoke to a Gentleman on the 26th of April by the name of Trevor who was assisting me in increasing my overdraft, he then explained to me that I cannot do this within 30 days as I had already decreased this on the 27th of March and need to wait atleast one more day, I then called back on the 28th April to sort this out only for the lady to tell me that I need to wait another 30 days as I made an application on the 26th of April??? There was no application done as Trevor had told me that I would need to wait another day or two... I have been on the phone trying to speak to someone who can explain to me how this is even possible as I have not had the chance to even increase this as yet. I do not want a revolving loan!!! Please can someone sort this out and call me to increase my overdraft or I will have to find a bank that can. I have only had great service from FNB for the past 12 years and now it seems thats all coming to an end. Surely you guys are better than this. Please call me asap!