Hi,
Did you associate your network connection resource with your ExpressRoute Gateway and ExpressRoute Circuit?
The status will only appear as "Connecting", "Connected", etc. once the configuration is completed.
More information on how to do this can be found here:
https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-linkvnet-portal-resource-manager
Cheers,
Stephane
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