Captive Portal not opening in Safari (iOS 13.3.1)

My company is providing WiFi access to our customers. When user connects to Wifi, the Captive portal (redirecting users to our web app) should display automatically.

This was working before iOS 13 on Safari browser. Now, what ever we try (entering some web addresses in hope that captive portal will load on this kind of actions), nothing helps.

What loads captive portl in Safari are the following actions:


What changed in iOS 13 (or Safari) because it is working in "Chome" browser on iPhone iOS v.13.3.1?

Captive Portal not opening in Safari (iOS 13.3.1)
 
 
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