cURL error 28: Operation timed out after 15001 milliseconds with 0 bytes receive

HTTP GET to this address timeout `https://www.usabilitydynamics.com/
?wc-api=am-software-api
&request=ping
&product_id=wpcloud%2Fwp-stateless
&instance=
&licence_key=
&platform=wp-network.ngxson.com
&nocache=56874
&version=3.1.1
&detected_products=W10%3D
&multisite=1
&stateless_media=21`

Caller: UsabilityDynamics\U\API->request()

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