VITAMIN b12 deficiency

I have had a very sensitive tongue (esp on the tip) for the past one year, due to which it gets burnt very easily. Once every month I get painful blisters on the tip of the tongue due to which I have problems with salty/spicy food. On blood diagnosis, I was found to be Vitamin B12 deficient, which was told to be the cause for the above-mentioned tongue problems and occasional stomach upsets/flatulence. My vitamin B12 levels were found to be 81 pg/ml and I was told the ideal amount is around 200-300 and my folic acid level was 5.7 ng/ml, which I was told was normal. On evaluating my reports, my doctor recommended Neurobion forte (fixed-dose B1 + B6 + B12) and Folly (Folic acid tablets 5 mg) tablets to be taken twice a day to control my B12 deficiency.

1. My first question is whether folic acid tablets were required even though I am not folic acid deficient? (My doctor tells me that it enhances absorption of B12).

2. On looking up Neurobion forte on search engines, I was shocked to find out that there has been a ban on Neurobion tablets in many advanced countries and that Neurobion forte is a name change to evade the ban. Why is this tablet formulation banned?

3. Will it be better for me to take only Vitamin b12 tablets instead of this formulation of B complex vitamins? Can you please recommend any particular safe brands?

Thanks.