FNB Home loan department whimsical nature

hi I have FNB home loan. It had a facility of flxi home loan facility, where i could deposit extra money to account and can withdraw whenever needed. When i took FNB Home loan it was one of the important thing which i ask for. FNB gave me that facility and i was using this facility for an year and half. All of sudden FNB disable this facility without any notification. And reason give to me, is because i am foreign national i can't have this facility. Where as it was active and i was using. When asked was such rule is been change is done recently, answer i got it was not it is rule form day one. So my point is if there was such a rule why i was promised to get that facility and why same facility was active on my account for year and half. is to just get customer and they FND does whatever they wish they can.