Had HI messages this morning 1 hour after Metformin 1000mg and Gliclazide 80mg. Had breakfast (yoghurt and muesli) after 1 hour still HI message. 2 hours later still high so took more Metformin and Gliclazide. 3 hours later still reading 22.2 on my Optimum xceed. Any suggestions! Does my machine need Central Solution Testing? I am 86 and have had diabetes for about 16 years.