iPhone shows SOS, No Service or Searching

• Estimated time: 2 min
• Easy
• Low risk

One reconnection; then compare the scope.

1. Outside a call and with network available, enable Airplane Mode for at least 15 seconds, then disable it. Check the affected line’s status. If service returns and does not recur, stop; temporary recovery does not identify the cause.

2. If unchanged, choose location, line or device state using the comparisons below. Do not delete an eSIM to repeat activation.

• Estimated time: 5 min
• Easy
• Low risk

1. Use observations from places where you normally have signal, without traveling somewhere unsafe to test. If it fails only in one building or area and returns outside, prioritize local coverage. If other users on the same carrier fail there, check carrier incidents.

2. Ask the carrier to confirm an active account, coverage, no restriction and plan/device compatibility. A confirmed incident or account restriction stops local testing. When traveling, check roaming and charges before enabling it; do not try to bypass restrictions.

• Estimated time: 5 min
• Easy
• Low risk

1. In Settings > Cellular (or Mobile Data), open the affected line and confirm Turn On This Line. If missing after changing SIM/eSIM, contact the carrier to complete activation; use the related guide for No SIM or Invalid SIM.

2. With Dual SIM, check both lines outside a call. During a call the other may show No Service due to Dual SIM operation; if it returns afterward, do not treat this as permanent loss or reset networking based on that observation.

3. If one line stays without service while the other works, give the carrier the affected line and change timing. This makes total cellular failure less likely, but does not rule out a SIM, provisioning or band-specific problem.

• Estimated time: 10 min
• Easy
• Low risk
• Restart required

1. On Wi-Fi, open Settings > General > About and accept a carrier settings update if offered, especially after a SIM change. If service returns, do not continue with resets.

2. If it persists, restart normally once to rule out a temporary state. If an iOS update is pending, back up first and follow its power and space requirements. Check whether the same line returns, not merely whether Wi-Fi works.

3. If the carrier confirms the line and network are correct and failure persists in covered locations, request Apple diagnostics. On iOS 18 or later, the Apple Support app may offer additional diagnostics. Do not delete the eSIM or repeat resets without a new hypothesis.