Due to a system error or scheduled maintenance, we couldn't process your payment can anyone help?
You can wait 24 hours and try again. Also, try logging out of your Google account, clearing the web browser cache, turning off any browser extensions and seeing what happens. I would try a different web browser, too, to help with troubleshooting.
If you cannot clear the issue, you will need to open AdWords, click on the gear icon in the upper right hand and calling the phone number shown or clicking on Help (same location) and using another method to access support so they can access your account with you and determine what is causing the issue. No one here can access accounts so we cannot dig into the technical reason why this is happening specifically.
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