ATR - ValueError: The truth value of a Series is ambiguous.

Hi
I've got 
ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().
when tried to get ATR using  ta.volatility.average_true_range(h, l, c, 2, False).

I managed to get this indicator several times before during the last half a year, but when I tried to run it yesterday I got an error.
Tell me what direction to look to fix this