Early debit orders

My application clearly states that, I am getting paid on the 26th of each month. Today is the 17th their debit order went off and it was unsuccessful obviously, this has caused me unnecessary bank charges. I keep getting messages that for the duration of the loan...my debit order will go off on the 24th of each month how? Where am I going to get the funds on the 24th because am getting paid on the 26 unless they fall on a weekend. Kindly assist. Busana