@alexapoc : in your example is the “server” your cellular connected device or an actual server (say something hosted on AWS).
If your server, the thing receiving http requests, is the actual cellular connected device I would recommend reading the post and my response at: Hologram Nova/BeagleBone Black/Web App Access
In general I would not advise running webservers on your cellular connected devices for many reasons. It may be ok for “proof of concept” but you will be massively overpaying for data and have lots of headaches and reliability issues if you can get it to work at all.
If your cellular device is issuing the “posts” and the cloud server is receiving them, then you can do it directly, you dont have to use hologram cloud messaging at all. It looks like you are using a Nova (based on you using Holograms CLI) and with that you can route any and all internet traffic through the Nova and make outgoing requests to an http server as if you were connected to wifi.