The worst service I have EVER encountered.....

Its SO unfair.... I did nothing wrong.... Besides being out of pocket, Im lost for words... I order a part.... I drive all the way from Germiston to collect the part... I pay my mechanic lots of money to fit the part supp**** by Spar on spares.... to find its an ****py inferior part that will never work... I pay the mechanic lost of money to put the old part back... I drive all the way from Germiston back to Spaar-on-spares to return the inferior part back... I was issued with a credit slip, and was assured that I would get a better and correct part. I drive all the way from Germiston back to Spaar in spares to collect the correct part..... to be told that I will not get a refund, nor the correct part on the basis that my mechanic fitted the part that was originally supp****... I did nothing wrong.... The worst service I have EVER encountered.....