Just to add on what Darrel suggested, try SSH into the AP and check if AP is negotiating to 802.3at power.get power-mode
if output shows that it is negotiating on 'af' then force the AP to get 'at' power using below command (assuming that your switch supports 802.3at).set power-mode at
Above is the chart from data sheet, which shows Power vs Operation characteristics of R720.
Also run below command to check eth port status, after connecting a device on 2nd port of R720.get eth
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