Doubled my money?

I received an account for my investment account. Somehow since last month, my balance has more than doubled. Since I only deposited R500 and interest was R98 (which is all on the account) how is this possible?<br> I tried calling the call centre but no one picks up the phone.<br> Please call me to explain how this is done and what my actual balance is. This is a HUGE mistake on Nedbank sides. As usual