I purchased a serger **T***DC Professional * Thread Serger about * months ago. This mac...

I purchased a serger **T***DC Professional * Thread Serger about * months ago. This machine did not come with the knife cover* item ** on page * in the instruction book. All I can do with this machine is a coverstitch. I did not buy this machine just to do a coverstitch. I bought it to do All of it's capabilities, but I can't without this part. I have spent hours and days trying to find a dealer or parts supplier that I could get this part from. They all tell me it's not available. It makes me angry that y'all would produce a product like this and leave a very important part out and not even make it available to get anywhere else. Please do not ignore this message. Please let me know something. Thank you for any help you can give me.