How did Mary die?
Tradition says that John cared for Mary after Jesus death.
One tradition says John and Mary moved to Ephesus in her last days and she died there of old age. Another tradition says she died outside Jerusalem. Tradition puts her age between sixty and the early seventies when she died.
One thing is clear. The Bible is silent on the subject.
Mary is not the focus of the Bible. The Bible authors did not want her to be glorified and eclipse Jesus in people's eyes any more than they wanted themselves to be elevated in people's eyes.
We are to look to God and pray in the name of Jesus alone for what we need. Although it is possible that some bored saint might be watching what is going on on earth and ask God to help out, praying to them is pointless and against scripture.
Our prayers are to be directed to God in the name of Jesus (John 14:9-14, 15:16, 16:19-28). Even if you look at Jesus model prayer, it is directed to the Father in heaven and not to those who have died before.