How much slow acting insulin

I am type 2 and living in France, my DR really is rather hopeless and seems to have little understanding of the condition. I am pretty much trying work out what I need to take. I am on slow acting insulin and currently taking 20 units in the morning, ( I would be very interested to know what other people are taking) I have slowly been increasing the dosage. I have fast acting which with experience have a handle on this. But I am about to run out. Dr likes to berate me about my levels but when I asked for fast acting insulin for my next presciption he said the pharmacy has run out and he is not sure why I need it. BTW this is not a language problem. Bit of a loss what to do. Taking Metformin and Jardiance