Hello and welcome – sorry to hear that you are dealing with this all over again.
It’s possible that the dose increase might have been a little too high for you and needs to be tweaked.
However, ff there is some tissue left behind after surgery or RAI, there *is* a chance that the thyroid tissue can regenerate and cause a return of hyperthyroidism. If that is indeed what is happening, you have the same three options as before – antithyroid medications, surgery, and RAI. One caveat is that there is some additional risk for a second surgery.
Blood tests – TSH, Free T4, T3, and antibodies (TSI or TRAb) should help shed some additional light on what is going on.
Take care – and keep us posted!