I NEED THE INTEREST RATE ON MY ACCOUNT BEFORE LOCKDOWN

I need to know the interest rate on one of my accounts, as it was before lockdown. It is a call account and the interest rate varies depending on the balance on the account. one person did send me a statement showing the interest rates for the past few month. the balance on these statements is more than R40000. I need to know what the interest rate was if the balance was R20000 or less. I need this to calculate a refund that I must do. it has been 4 days and just no one seems to be able to give me this interest rate