ESP32 cloud access works locally but fails once hosted via international partner

[Kambel]

Hi all
I set up an ESP32 with a simple web dashboard and MQTT reporting for a small client project. Locally everything works fine on my test router, stable WiFi and clean data push. I expected it to behave the same once we moved the backend to an international hosting partner to structure the business side and scale it properly, but the ESP32 keeps dropping the connection after a few minutes. Nothing changed in the firmware except the server address. The only real difference is the hosting environment and their firewall rules. I’m not an expert in network infra so maybe I missed something obvious. Has anyone here had similar issues when moving an ESP32 project from local network to a cloud partner setup?

[MicroController]

the ESP32 keeps dropping the connection after a few minutes.

Might be helpful to clarify what you mean by this. I.e.
1) What connection breaks? Connection to the WiFi or to the broker?
2) Does the ESP32 "drop" the connection, or the broker, or some network infrastructure?

Looking at the ESP's logs should help in identifying why/where the connection is "dropped".

[Kambel]

Cheers for the quick reply.
To clarify: it's the MQTT connection to the broker that’s dropping, WiFi is rock solid. The ESP32 just keeps trying to reconnect in a loop. I’ve had a look at the broker logs over on daftime.ae, and it looks like the packets are hitting the server but getting binned or severed before they’re accepted. Pretty sure it’s a firewall issue or some weird keep-alive behaviour compared to my local setup. Any ideas on what specifically to look for with the firewall settings? Don't want to go poking around if there's a standard fix I'm missing.