Q: Can we ask the Prophet sallallahu alaihi wa sallam directly for help?
A: It is Haraam to ask the Holy Prophet directly for anything. Yes it is permissible to go to his grave and ask him to intercede for one by Allah, or ask him to make Du'aa for one by Allah. But this can be done only in front of his Blessed Grave and not from afar. This is mentioned in the books of all math-habs.
And Allah knows best.
Mufti Siraj Desai