Water do not come out of the center fixed outlet of water faucet

[albertkao9]

My water faucet in the kitchen has two outlets - the center fixed one and the flexible side one (see photo).
Water do not come out of the center fixed outlet.
Water come out of the flexible side outlet only.
How to fix it?

 

[Snoonyb]

On the faucet should be a manufacturers name near the escutcheon plate, on the swing-arm.

Shut the water off at the angle stops under the sink. On the control lever you'll find a screw, which may be under a removable cap, which you loosen, and might remove, which allows you to remove that handle. You'll either be able to remove the faucet cartridge, or you'll need to remove a retainer cap to access the cartage.

 

[Snoonyb]

OOPS!, My apologies, I forgot to mention the aerator, which is the 1st place you look, because they often become restricted by calcium debris.