Rude and disrespectful

Worst service ever ,I place an order on Mon/Tues and I was told the part will be delivered on Friday to which I made arrangements to have my car by the panel beater when I send an email to the guy by the name of Daylan he confirmed that part will be delivered on Friday,now all of a sadden they are saying the part will be delivered on Monday,they are blaming the courier,very rude and disrespectful