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Probably, the screen on the end of the faucet is plugged up with calcium debris or sand particles. Unscrew it off there and clean it out. IF you have compressed air that would help. MOST come apart, so be careful to get it back together the same way. Make a diagram or take a photo of the parts. We see this question quite a lot here. IF it resists coming off OR if you have a hand wand, you may need to use a pin to open them back up and blow it out from the discharge side. That would take some compressed air. Try that and then get back to me if you need more as all follow ups are included in our fee.
It may be some debris IN the valve.........is this a single lever faucet? Those are more prone to to this problem. Very small orofices in those.
OR the vavle body gaskets are coming apart and jammin up in there.
Some of those have intake screens in them. IF you take the valves out and still have no flow or poor flow, check that. You would need to remove the fixture. IF you do that, you might want to consider upgrading to a single valve unit.
Were you able to track down the blockage on this? Let me know if you need help upgrading to a newer style.............