Gliclazide can cause hypo's. Canagliflozin can cause hypo's in combination with gliclazide.
You haven't had problems in the last year but I understand you haven't followed a low carb diet during that time? This makes a lot of difference! Please take your hypo's seriously when on those medications, call your doctor tomorrow to discuss your readings and your medication regime. In the mean time, treat your hypo's when you have one.
And well done for getting lower numbers by adjusting your diet, now get you GP to to help you find out the right adjustments to your medication!
Do you drive? The UK has pretty strict rules on hypo's and driving, plus, our brains don't work too well when hypo. It's like driving drunk, even if we feel perfectly capable.