What is diameter signaling and why should you care

Diameter is the protocol used for authenticating roaming subscribers. If Openline's diameter link to a partner has an outage, activation temporarily fails in that country. Rare but possible.

Further reading

Still stuck?

Reach Openline support 24/7 through any of these channels:

When you write in, include your purchase code (the OL-… code we emailed you) and, if the eSIM is already installed, its ICCID (Settings → Cellular → tap the Openline line). That's enough for us to find your plan and diagnose without back-and-forth.