I agree with everything said above, as harsh as it may sound. White's can withstand a lot of error in there care, however, there is a limit. Just because the frog didn't show signs of ill health prior to your receiving it, does not necessarily equate to proper conditions. My guess would be it was improperly cared for from day one and you were "grandfathered" in. The twitching could also be a sign of calcium deficiency. I would definitely switch to crickets as a primary food and dust with each feeding.
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