SD Card stopped working Technician made things worse

I bought my laptop less than a month ago. The SD card slot suddenly stopped working. The computer itself worked fine and was still useable. A repair person came to my house to fix the issue, but the motherboard he put in didnt work at all! Now I'm stuck with a non working computer that I have to mail in! 

I should've just fixed the minor issue myself instead of dealing with Dell customer service! Just like all the other millions of complaints, you quality control is horrible! I should've spent my money somewhere else!