I am getting 2 to 3 female patient (vegetarian) age range 20 years to 55 years with complaints of weakness, tiredness, bodyache with tingling with headache which was investigated n found to have Vit. B12 deficiency rest all lab ix normal including FBS n pp2bs n u/s, thyroid profile those patients were treated in the form of injectable vit.b12 with oral supplements but these patients are repeatedly coming with same complaints every 6 months n everytime Vit.b12 level low rest all normal.so please guide me for further investigation and management.