Is this a new pool and a new issue? Depending on your mfg. the jets can be unscrewed from the spa side. You have to first unscrew the return eyeball or whatever is against the plaster. Then usually about 6-8 inches back in the pipe is a jet. It may have a hex on it where you can put a 6 point socket over it with an extension bar and unscrew it. Once out, flush the pipe for any debris.
this is what my jet looks like but every mfg. Is a little different
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