I had a similar problem with my left leg and foot quite recently. I have no idea what caused it, but I tried two things, both of which seem to have brought about a recovery:
(1) I used the Spooky2 Healing & Regeneration preset, plasma mode, putting the plasma (phanotron) on the soles of my feet. This seemed to kick-start the healing process and was extremely soothing.
(2) I returned to Pilates classes, which I had neglected for several years after changing residence.
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