Your FT3 certainly is very low. Not surprising you still have symptoms! But, your really do need a range for that FT4, otherwise we cannot see how well you are converting.
12 on most FT4 ranges would be pretty low. But that's a stupidly small increase your endo has given you, and hardly likely to help if your FT4 is very low.
How do you take your levo? On an empty stomach, leaving at least one hour before eating or drinking? Do you take any other supplements or medication at the same time?
Unless you know for sure that the analysis was done in the same lab, and they haven't changed their ranges since, the range on an old letter won't be much good. Could you not ring the endo and ask?
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