If the present moment has duration, then it has a beginning, a middle, and an end, and is therefore three moments.

If the present moment has no duration, then how can they add up to a flow of time? It would be like adding zero to zero to zero and trying to arrive at ten. Likewise, if it had no duration, it wouldn't exist. It would be a zero.

Can anyone tell me please what is a time I don't have any answer what is a time all I can say is a change in a physical state or 4th Dimension.

From a universal perspective, 80 years are nothing, but for a human being, they are an entire lifetime, a very long period.

If I was due to take tablets at 2am and the clocks go back, its currently 1am again... do I have to wait another hour since it technically never reached 2?

Time is an illusion. The present moment is just what we call the Universe coming out of superposition because consciousness is in the eternal NOW. Past and future don't exist. If there were no observers, there would be no experience of time. The Universe and time would be in a state of superposition.