New user of blueshift here.
I am trying to play around with the bollinger band template. It didn't find the Nifty and BankNifty symbols, so I replaced one with SPY and I tried numerous other ETF, but all of them throw up a not found error. I am using NYSE selection. Whatever I try, whatever other ETF than SPY i try throws up the same error.
Blueshift at present does not cover ETFs. Please see here for dataset details. We have a plan to add ETFs for the US market sometime this year.