You will need to identify the exact point of failure. The best way to do this is to run Attachment 31 (Q500 Binding Verification) of the PDF document attached to the Way To Fix Drones project thread. There are some prep steps at the front that must be followed carefully. The sequence then leads to a series of "action" steps, each followed by a step to verify the results of the action. When you find the step that does not match it's verification, or you are not certain, stop and report the step number and what result you actually saw back to the forum. We can use that information to help determine the issue.