Wiki injection J0702

[akaeb]

I have a family practice clinic that did an injection of 18 mg for J0702(injection, betamethasone acetate 3 mg and betamethasone sodium phosphate 3 mg). Would you do quantity 3 or would you do quantity 6? I read it as you would do quantity 3 since the combination of the medicine orginally makes 6 mg or is this incorrect?

Thank you!