how do I solve the Error in get.current.chob() : improperly set or missing graphics device

Whenever I run the following code:

chart_Series(`BTC-USD`,
         type = "candlesticks",
         subset='2017',)
addSMA(n=30,on=1,col = "blue") ,

It gives me the following error:

Error in get.current.chob() : improperly set or missing graphics device