I'm not a B12 expert but logic tells me that if you have a high level of B12 in your blood, you are absorbing it but maybe not able to utilize it. There are others here with more knowledge on this.

Acid reflux....are you taking anything for it? Acid blocking drugs interfere with B12 absorption. Have you been checked for H-pylori bacteria? Do you take a good probiotic or eat cultured foods? Bacteria imbalance can cause problems.

You stated that you did not start taking the Jarrow methyl form until after the test so if it's a conversion issue, retesting in a month or so may be in order.