Hello Bashar, I am one of the engineers from the Small Business team.
I have reviewed the RouterBOARD manual 1100 and was unable to find something related with the VLANs. Let me ask you if you connect a computer directly to the RouterBOARD are you getting the IP address?
Try to do a factory reset to the unit (hold the reset button for 15 seconds), connect the WAP371 to your router one more time and confirm on the DHCP options on your router what IP address was assigned.
Confirm if you were able to solve the issue.
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