non existent next day delivery

I ordered a birthday present for my grandson at 8.50am for next day delivery at cost of 3.99 then got an email to say it would arrive a day later than I had paid for , emailed on several occasions but only got automated response . Had to change delivery day with Dpd to my next day offas no option for Sunday .
If I could give a minus star I would normally spend 5-600 in Xmas period will go elsewhere from now useless incompetent ignorant . As a store manager I know what is and is not acceptable and this is far from it . -100% if I was a mystery shopped .