I am on Talk Lite and did not use Talk this month, however, I was still charged $1 for usage?
The cost for the Talk Lite subscription is $0 per agent, however if you have an active phone number on the account you are charged each month based on the number.
The price of a phone number depends upon the country from where it was purchased. For example, local numbers from US and Canada cost $1, while toll-free cost $2. For a full list of prices by country, see Zendesk talk number availability and pricing.
If you want to delete your Talk number and not receive this monthly charge, see Managing Zendesk Talk numbers.