When I start descent at TOD the ATC constantly tells me to climb back to previous altitude, ie climb and maintain flight level 150. If I do this I miss the landing by a country mile, any help?

You need to wait until cleared to either descend to a new altitude or descend via a STAR before you start the descent.  If you need to start earlier, then you should use a slower descent rate in your Flight Plan.

P2A recalculates your TOD during cruise and if you are flying slower than planned, the ATC TOD might be a little later than the one on the map.  Also, it rarely matches the one on your FMC if that's what you're looking at.  Changing the Descent rate in the plan will often get these two to be closer.

Regards,

Dave