Hello, i am struggling to understand this.

High nominal interest rate rises the real interest rate, so the opportunity cost of holding the money becomes greater, so people would spend or invest the money, the velocity of money increase and mv=py so less money suppy mean less siegnorage,

when there is high infaltion, the real interest rate decreases, so the opportunity cost of holding the money becomes smaller, so people keeps the money in hand so decline in money supply and less seignroage ?? but now the borrowing cost would decrease so people would invest and increase in demand for money so more seignorage? i am confused which is which?