Why isnt my touch pad and usb ports working?

I recently disassembled my laptop when and i put it back together the touchpad and usb ports stopped working,the usb ports dont respong to anything that gets plugged into it and the touch pad isnt working either,the keyboard and rest of the laptop do work fine though, i tripple checked that everything was in place i dont think i missed anything , help?

HP probook 450 g1