Why is there a charge when no answer arrived?
You should not. Nudge only captures the payment when the coach sends a reply, so a charge without an answer is either a pending authorization or a mistake worth reporting.
Check this first
A pending authorization on a statement looks like a charge and is released when the question expires. If the amount has actually settled and no answer arrived, contact support with the date and amount.
60 answers in the Nudge help centre.