For starters, your B12 is waaay too low, and from your post,
seems to be lower than the last time it was tested.
Any B12 below 700 (some say 600) is suspect.

Docs who do not know this,
have been taught from texts 20 yrs out of date!

You may have a B12 malabsorption problem.

Recommended :
Methyl-cobalamin B12 (not cyano-cobalamin)
in amounts of 2000 to 5000mcg per day
for at least 3-5 months, then test again.

My B12 stays in the 1200 range with 1000mcg per day maintenance dosage.