Everything was fine before they froze my account without letting me know or ask me where they money I received comes from

Disappointing experience with FNB. My account was frozen due to a reported *****ulent transaction of R400 without any prior notification or verification. No attempt was made to contact me to confirm whether I was aware of the transaction. This lack of communication caused unnecessary inconvenience. I hope the bank improves its security protocols and customer service. When they will unfreeze my account because I have sent them several emails but they don't respond even on their Facebook page😏🙄