Debit that is untraceable

ON the 27th July 2019 the was a pending debit on my account when i went on to the banking app i immediately contacted Nedbank using the banking app chat and was assisted by Carl who advised me that i should wait till it clears on Monday being the 29/07/2019 , Today on the said date i make a follow up and am assisted by Anele on the chatting app and she advises me the amount is not traceable and that now my amount is also about less that the actual amount , to make matters worse the debit has gone through and deducted from my account even though its not reflecting , so am not sure what nedbank has done in my account