I accidentally dropped a drop of regent into the middle of the blue alk reader and twisted a paper towel and dabbed it up. Now my reader does the 1st reading and on the second with regent added just blinks --- or gives me the LLO low light error. Changed battery to let it reset but no go. Can I take a Q-Tip and alcohol and clean inside that tube or what else should I do? Vials are fine. I handle with an Oakley cloth.