Problem: You can not login from the device.
The first thing is to test the endpoint.
Copy the URL to the endpoint
On the device navigate to the browser and paste it to the URL
If it does not work, you will get an error.
If the infrastructure is working properly, you should get an answer like this one below. "You have created a service".
Solution:
Your device is not able to access the endpoint. This has to be solved by the IT responsible. It could be a port has not been opened or the network, the devices are using, is not properly setup to communicate with the ERP server.