Sly tactics from Incredible Connection

Purchased an item online and they refuse to give me the item for the advertised price. Firstly they tried to shift the blame on me by saying I canceled my order, which was very dishonest of them, I rep**** that I didn't cancel, and conveniently in the next email it was a mistake on their system... The "mistake" was on the system for a while. They outright refusing to give me the item now for the price I paid. It's not the 1st time I'm having an issue with the company. Days before I made my purchase online, I was at their N1 city branch and the *********** boy they have as a store assistant wasted my time when I tried to buy a tablet... He told me it will take 10mins to get the tablet from the safe, I understand this, he told me to either wait or I could come back in 10mins...he also told me that he would keep it out if I wasn't back in 10mins as I told him I'm defnitely gonna take it. I came back after 30mins and he told me he forgot and I should wait another 10mins. Have read of reviews claiming a **** is being run with this company.