Hello,
Are you able to access the device locally on HTTPS port?
Maybe the device has some requirement to enable access from WAN, as in case of Teltonika devices?
Also, when it comes to reaching devices through HTTP(S) RMS Connect functionality, some particular device WebUIs might not load correctly or not load at all, because they might have unique WebUI aspects, which does not work properly when accessed through proxy.
As for the remaining data, this section applies, if you have packs bought, instead of separate credits.
Best regards,