When I tried to activate Solemn Notice/ Solemn Strike - ( In the data it says Solemn Strike, but on the card it says Solemn Notice.) - For a fusion/ Synchro summoned monster, after the summoning and the materials were sent to the graveyard, the materials activated instantly, only giving me the option to negate the materials effect from the graveyard and not the synchro/fusion summon it self.

Could you specify the actual Fusion or Synchro cards in question?

Solemn Strike can only negate summons that do not start a chain. This includes Synchro Summons, but does not include most Fusion Summons as they are usually summoned with another card.

Solemn Warning can be used to negate the initial activation of the usual cards that perform a Fusion Summon, but once the monster is actually summoned, you can no longer activate it.