How can we help?

The questions we are asked most, for Android and iOS.


  • Let's check the install one thing at a time.

    Did you install the eSIM without Wi-Fi?
    An eSIM has to be installed on a stable Wi-Fi connection.
    Did you switch the line in use to the eSIM you just installed?
    It is easy to confuse it with an eSIM installed earlier, or to forget to move the data line off your old SIM. Please check again.
    12:14
    12:1430 August
    Wi-FiBluetooth
    CallsSIM 1o2 - deMessagesSIM 1o2 - deMobile dataSIM 1o2 - de
    Swipe down in the direction of the arrow to open the panel.
    12:14
    12:1430 August
    Wi-FiBluetooth
    CallsSIM 1o2 - deMessagesSIM 1o2 - deMobile dataeSIM 1CMLink
    SIM 1o2 - deeSIM 1CMLinkNo number
    Switch to the eSIM you installed.
    Did you turn on data roaming?
    Open Settings → Connections → Mobile networks and check that data roaming is on.

    If the eSIM still will not activate, contact our support team.

  • Sometimes the install finishes correctly but the phone fails to pick up the network details and the connection drops. Try these in order.

    eSIM troubleshooting checklist

    1. Sign in to eSIMmu and check the expiry date of the eSIM you bought under Remaining data. It may already have run out.
    2. Open Settings → Connections → Mobile networks → Network operator, turn off automatic selection for the eSIM, then try the available carriers one at a time. When one connects, the problem is solved.
    9:30

    Network operator

    SIM 1eSIM 1
    Select automaticallyLets the best mobile network be chosen for you. With this off, pick one yourself from the list of available networks.
    Turn off automatic selection under Network operator.
    9:30

    Network operator

    SIM 1eSIM 1
    Select automaticallyLets the best mobile network be chosen for you. With this off, pick one yourself from the list of available networks.

    Available networks

    o2 - de
    1&1
    Telekom Deutschland
    vodafone.de
    Try the available carriers one at a time and stay on the one with a working connection.

    If that does not help

    Turn airplane mode on, wait ten seconds, turn it off, and repeat two or three times.

  • Sometimes the install is fine but reception makes the connection slow. Try these in order.

    9:30

    Mobile networks

    Allow 2G service SIM 1Use 2G networks in areas with no other network available. Emergency calls can still use 2G even when it is not allowed.
    Network mode SIM 15G preferred
    Network mode eSIM 1LTE preferred
    5G preferredLTE preferred3G preferred
    Access Point Names
    Network operator
    Change the network mode to LTE preferred and test.
    9:30

    Mobile networks

    Allow 2G service SIM 1Use 2G networks in areas with no other network available. Emergency calls can still use 2G even when it is not allowed.
    Network mode SIM 15G preferred
    Network mode eSIM 13G preferred
    5G preferredLTE preferred3G preferred
    Access Point Names
    Network operator
    If that does not help, try 3G preferred as well.
    • Open Settings → Connections → Mobile networks → Network mode, switch to LTE preferred, and if that does not help try 3G preferred.
    • Open Settings → Connections → SIM manager, turn your old SIM off for a moment and test the speed. If it improves, you can turn it back on.

    Interference, or the combination of phone and network, can also make things slow.

  • This notice usually means the phone you are using does not support eSIM.

    How to check

    1. Open Settings → Connections → SIM manager.
    2. Look for an Add eSIM entry in that menu.
    • If you see it, your phone supports eSIM.
    • If you do not, this phone does not support eSIM.
  • Yes. Whether you buy as a guest or with an account, the eSIM is ready on the site the moment payment goes through, and you can install it from there.

  • eSIMmu is a data-only eSIM, so it carries no phone number for calls or SMS. Calls over apps like WhatsApp, KakaoTalk and Facebook work as normal, because they run on data.