Numbers 12:13

‘And Moses cried to Yahweh, saying, “Heal her, O God, I beseech you.'

So Moses heard their plea and prayed to Yahweh and begged Him to heal her. Note that his prayer was to ‘God', not ‘Yahweh', recognising that by her behaviour Miriam had put herself outside covenant promises. Moses is ever the final intercessor.

How we should rejoice that we have an even greater intercessor, the One Who lives ever to make intercession for us (Hebrews 7:25). But it is not intercession that our sin be overlooked, but rather that we might be saved from it. It is not an intercession that leaves us as we are.