If you purchased your Calling or Audio Conferencing plan through a Cloud Solution Provider (CSP), you can't acquire Communication Credits in the Microsoft 365 admin center. Your CSP needs to fund Communication Credits on your behalf.
If you want the ability to fund your Calling or Audio Conferencing plan with Communication Credits on your own, purchase your Calling and Audio Conferencing plans from the Microsoft 365 admin center or the Microsoft sales page yourself.
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