Hi S
If you are sure your Bolus to carb ratio is right, it looks like it is probably the wrong choice of food for you at that time of the day. Cereal bars are usually very high in sugar and low in fat so are in essence a fast acting glucose.
The cereal bar will be kicking in quick before your insulin does and raising your BG rapidly ,this is staying high and along with other hormones on a morning is keeping you high. A lot of us have a higher insulin to carb ratio on a morning because of the Liver dump and Cortisol rise to get us going for the day....let alone the Adrenalin to get us through the rush hour to get into work :shock: These all raise blood sugar.
Maybe change your morning ratio's if you still want to carry on with the cereal bar...I low carb and find mixed berries and cream is a good breakfast to keep me stable on a morning ,but why not have some porridge with half cream half milk...this may keep you on a steadier profile. Granola with no added sugar is good.
What about fruit and a yoghurt ,higher carb than cream but an option.
Just a few ideas, if you fancy low carb on a weekday and don't have the time for the grill or frying pan, how about hard boiled egg with some good quality ham...continental styley
You will just have to experiment a bit more...all the best and I hope you find a solution.