Airtel - Collecting extra money from me

Actually, I did a recharge *** on the **th of June at nearly *:** pm. That transaction failed. I call the customer support and ask about that. He told me your recharge is failed. That failed amount will be refunded in your account within *-** days. After that, he told you have to do it again. After that, I do again. Recharge is successful. After nearly *hrs later that failed transaction also activated.
Why it is activated that executive already told to me that amount is refunded. Please do again' that's why I'm doing again. Also, that network is too slow and call the breaking middle of the cal very bad network in recent times
Totally I lost *** (***** =***)
One recharge for ** days is ***
But they play a tragedy to customers.