Bank Account at RISK

Money was deposited into my account ,i used it thinking it was the money i was expecting from my former employer,two weeks later a guy from a company called Peter Peter Sugar called saying they deposited the money by mistake and that they got my number from Shereen King who works at Standard Bank Claims department,but when i checked the company,it does not exist.On the 13/05/15 i received a call saying i have been selected for a SPAR competition so i should give them my Id number and address i refused and said they should send me an email with a letter head,thats when i realized it was a ****.Today i received a call from a guy claiming to be a police saying the same thing the PPS guy said and that the person who is claiming that money will call me,she did not call,she sent me an email with an agreement form for me to sign and that form had that false address i gave the lady who called me claiming that she was from SPAR only now she is claiming to be K.Hattle from Life Health care.I do not not know what is legit and what is not anymore all thanks to Standard Bank employee and it is evident that all our accounts with them are not safe,they should have contacted me as their customer!