A SIM card is an obligatory element of communication installed in all mobile phones, however, some of their owners are faced with a situation when their device no longer sees a SIM card. Some of the causes of the problem can only be eliminated in the workshop, while others are easy to fix on your own.
The most common reasons
Almost all operators are engaged in the sale of products locked only for their communication services. That is, a phone bought at a discount in one specialized store with an already installed SIM card will not accept someone else's if its owner decides to change the operator. There are two ways to solve this problem: firstly, you can continue to use the services of the previously selected company, finding the most acceptable one in the tariffs it provides, and secondly, you can try to unlock and reflash the phone by contacting the wizard. It is not recommended to do the flashing on your own by downloading the appropriate applications via the Internet: there is a high probability that you will come across a paid program that will remove the old one, and, before the final installation of the new one, will offer to transfer money to someone's electronic wallet.
The second possible cause is oxidation or contamination of the slot pins. It occurs naturally as a result of long-term use and is eliminated by simple cleaning. A regular school eraser helps a lot. Plaque can also appear as a result of the contacts getting wet: having dropped a mobile phone into a puddle, its owner does not dry it too thoroughly, and after a few days he discovers that the device does not see the SIM card. The source of a temporary malfunction can be condensation formed as a result of a sharp change in temperature due to the transfer of the phone from frost to warmth. It is necessary to remove its cover, remove the battery and allow the contents to warm up and dry.
Over time, the connection of the SIM card to the contacts may weaken. In this case, remove the battery, pull out the SIM card and insert it back. A piece of paper folded several times between it and the batteries also helps, sealing the docking of the components. For smartphones, this element can be wrapped in a couple of layers with a paper strip, avoiding the contact area, and then, holding it, insert the SIM card into the slot.
When no intervention is required
If the phone number is not used for a long time: for a certain time, paid operations (calls, SMS) are not performed on it, then the operator blocks the SIM card. After that, the number connected to it is laid out in the database of freely sold ones. After inserting an element into the slot and finding a malfunction, you should immediately contact the cellular center and unlock the SIM card. It is often enough to put a small amount of money into your account. If the number is not transferred to another owner, there is every chance of returning it.
