It used to be quite easy, dialling 333 used to activate a text message from Movistar that indicated the amount of cash credit you had remaining on the phone. However, Movistar changed all that about a year ago and now send a text message when you have less than 3? left, then another when you have less than 2? credit. So far as I am aware the facility to request the credit balance no longer exists. When you recharge your movistar phone account a text message is sent out showing the balance available and the expiry date of that balance. After that date any credit remaining is forfeited. Each recharge extends the six month validity period of the total balance.
Credit in terms of minutes available was never an option as text messages and voice calls are charged at different rates.
hope this helps.
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