It looks like you need to have another internet connection that does not use Wi-Fi, as the hotspot will take over and use that for sharing the connection with other devices. For example, an ethernet cable or perhaps an additional Wi-Fi adapter.
I used WI-FI as hotspot yesterday in zorin-os.
And if you simply click on "Turn on" to enable the hotspot, does it work?
my laptop sharing wifi but without internet
I mean, I'm not an expert but that sounds like the expected behavior... you cannot make use of the Wi-Fi antenna for both receiving and sharing Wi-Fi at the same time. On mobiles, for example, you must use your regular internet connection as the source and the Wi-Fi antenna for hotspot.
Maybe you incorrectly assumed it was working before because you were connected to a different device or some content was cached or something?
Computer wifi cards only have one "radio". Your phone has multiple, at least two. You would either have to use a dongle or plug the ethernet cable into the card on the laptop. High end wifi cards may be able to transmit and receive, due to multiple radios, but are currently not standard in laptops.