If you have sent money from your Equity Bank account to the wrong Mpesa Number and you need reversal then you can contact Equity Bank through 0763026000 and select the reversal option. One of Equity Customer Care agents will pick your call and ask for your account number and phone number where the transaction was made to.
After making a reversal, it will take 24 to 48 hours for the money to reflect in your Equity Bank account.
Don't waste your time calling Safaricom because they will not help you.
NOTE: Make sure that you have confirmed whether the money has been withdrawn or not. If it has been withdrawn, then there is little that Equity Bank can do to help you.