Valve stem slow leak

[BamaInArk]

I bought a used 2020 Edge SEL back in Sept.   All good.   After about a month I got a low tire pressure warning.  Left rear.  I aired it up and lasted another 2 to 3 weeks then low pressure warning again.   So I started checking it more often(before a low warning alert).   It has a slow leak.   Well I finally removed the wheel/tire today to inspect for any punctures.  Nothing in the treads I could find.    So sprayed soapy solution all around the bead, both sides.  Nothing.  Checked valve stem needle....nothing.   Turns out it's the rubber valve stem itself where it's mounted into the rim/wheel.    I'm in my mid 60's and this is the first time I have seen a valve stem leaking like this.   I was able to wiggle the rubber slightly and seem to stop the bubbling momentarily.
Am I to assume about the only way to fix this is to take it to a tire shop for a new valve stem insert?   The tires appear to be the factory tires.    47000 miles.