beccam,
"The stellate ganglion nerve bundle carries sympathetic signaling to many body regions and organs, including the head, neck, upper limbs, thymus, heart, lungs, lacrimal gland, salivary gland, thyroid gland and pineal gland. Injection of local anesthetic near the stellate ganglion can block activity of the entire cervical sympathetic chain,"

You might try a stellate ganglion block. I is thought to reset the autonomic nervous system It has been commonly given for PTSD, for hormonal deficit hot flashes and excessive sweating. But has also been trialed for dysautonomia resulting from long covid and Lupus.
The procedure is a simple injection under fluoroscopy without setation that takes abou 15 minutes. Usually in the first procedure the injection is given on one side and the second on both sides. It may require multiple injections over a period of months.
Pain specialists are the most practiced in giving the block.
I hope you find some good medical help.