Certain Keys not working on Keyboard
I just replaced the MacBook 13" Model A1278 Unibody Upper Case(backlit) Order #138350, Part #IF160-001-1 that I purchased from iFixit and Certain Keys (A S D F G H J K L Z X C V B N M , .)are not working. I reseated the keyboard ribon 3 or 4 time's to make sure the problem wasn't there. I hate to have to take it apart and send it back to find out that it's a simple fix I could have done or missed. Please advise.
Thank you, Charles