Hi @miraz m,
Your AdWords account balance is charted in the billing section of your account.
Open up AdWords, click on the gear icon in the upper right hand corner and click on Billing. Now you will see all the main info about debits and credits, which is where payments and charges are charted. If a payment was successful, it will state that it was and show the amount paid in the credits column.
All the Best,
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