There seems to be an issue with how the Volume is being returned. Thank you for taking the time to let us know about this issue. We hope to have it fixed soon.
TradingChart can be a very picky function. When it doesn't work, you're usually best off using FinancialData. For example, sometimes the availability of data changes for reasons beyond our control. In this particular case, the "OHLC" data is all fine so you can still make a basic CandlestickChart from it.
CandlestickChart@
FinancialData["GOOGL", "OHLC", {{2009, 1, 1}, {2009, 12, 31}}]
