Luna: Did you replace the stock retention bracket with the one included?
That is
very important. Replace it and use the stock backplate if you have not already.
Also, try reverse bending the clips about 3-5MM to add a little extra downward tension.
For your reference, here is the
XP-90 Installation Guide.
If we can't get this issue worked out I want you to send it back in for a refund, and I'll pay
the 15% restock and return S&H plus difference so you can get something else, OK?