Vitamin B12 deficiency and small fiber neuropathy

Hi everybody,
I was hoping to possibly connect or receive advice. Has anybody been diagnosed with small fiber neuropathy caused by a vitamin B12 deficiency? I'm 28 years old and have always been healthy otherwise. I've never smoked, always maintained my fitness level, and have always had a relatively healthy diet. My B12 deficiency went unnoticed for 13 months, and I finally began getting treated for it about eight months ago. Doctors are hopeful I can recover but aren't sure. Does anybody have any experience with this? Any advice would be welcome. Thank you!