Smartphones purchased from a mobile operator are very often "blocked" on a single specific network. A negative point when you want to change mobile operator. How do you know if your smartphone is actually locked by a supplier? And how to fix it?
At first glance, this is not very important. However, when you want to change mobile operator or buy a used iPhone, locking a smartphone by a mobile provider can be very annoying. This is why it is better to ask your operator to unlock your phone if you intend to resell it or change your supplier.
How to check the status of an iPhone
The first tip to check if your iPhone is blocked on a single mobile network is to go to Phone settings, then to "Cellular data" and finally to "Select a network".
If you see the options "Cellular data network", "Mobile data network" or simply the network of several mobile operators, it means that your iPhone is not locked and that it can juggle between several networks.
A solution which is not always convincing, this is why it may be more interesting to refer to the IMEI number / serial number. This international identification number of mobile equipment makes it possible to know all the information relating to a device.
You can find this number by going to your iPhone Settings, "General" and on "About". The IMEI number should be there. Copy it and return it to a specialized site which allows you to verify that a device is locked by an operator. Unfortunately, most of these sites are paid.
Finally, you can also contact your operator directly and ask him the question.
How to unlock an iPhone
As Apple indicates , the only solution to unlock a smartphone is to request it from its mobile operator. Depending on the suppliers, this may or may not be chargeable, taking several days.
Once your mobile operator has confirmed that your phone is unlocked, you can change the SIM card.