A Delta ball faucet is adjustable. Remove the handle (you don't have to turn off the water.)
There is a plastic ring with two small gaps around inside the cap where the stem sticks out. If you don't have the Delta tool with the little prongs that fits into to those two gaps, you can use the ends of a needle-nose pliers.
Turn it clockwise to snug it down onto the seats-and-springs only so that it quits leaking. Do not over-tighten it as that will just make it hard to operate and wear out the seats-and-springs much quicker.