High rise spout on kitchen sink becomes loose when spout is swiveled from one sink to the other. The spout becomes so loose that it starts to separate from the sink.
Repeated attempts to tighten the plate and screw assemble from below have not been successful. No other items were provided to secure the individual spout.
What to so?

Can you tell us what the name and model of faucet? This will help us help you.

Chuck