i too make good trades early in the trading day......similar problem
i suspect it is because early in the day the charts are not cluttered or complcated...as the day progresses sometimes it consolidates and the charts get a lot conflicting swings...
if you know what i mean?
and it becomes more difficult to know which side it will jump.
i solved the problem, by only taking the very clear signals, later on..........markets are never THAT clear but i think you may know what i mean.
i mean even when the markets are clear it is hugely difficult to make money but at least at that time it is possible