"eSIM cannot be added" — what it means
Usually one of three things: already installed, a locked phone, or no eSIM support.
Three usual suspects, in order of likelihood:
1. The eSIM was already installed
Each eSIM installs once, on one device. If the install got halfway (or it went onto an old phone), the code is spent. Email help@fullbars.co.uk with your order number — we can check its status from our side and reissue if needed.
2. Your phone is carrier-locked
A phone locked to a network refuses other SIMs — including eSIMs. Check: iPhone: Settings → General → About → Carrier Lock (want: "No SIM restrictions"). Android: search "network lock" in Settings, or ask your network. UK networks must unlock your phone free of charge — it usually takes a day or two.
3. The phone doesn't support eSIM
Quickest test: dial *#06#. If an EID appears, your phone supports eSIM. No EID = no eSIM support, unfortunately. You can also use our compatibility checker. One gotcha: some models vary by region — iPhones from mainland China, for example, don't have eSIM at all.