This prompt indicates that there is a problem with the contact between SIM card and card slot. Since different devices have different contact positions with the SIM card, sometimes you will encounter such a situation. A SIM card can be used in other devices, but the card may not be detected on Cudy, and Cudy will Prompt SIM detach. Most of this situation is caused by poor contact between the SIM card and Cudy.
You can try the following methods:
1. Check that you use a correct SIM card, use a micro SIM card, or use a SIM card adapter convert a nano SIM card to a micro SIM card. (For LT450 V1, LT500 V1 only)
2. Check that you have inserted the SIM card in the correct direction. With the gold contacts (circuit side of the SIM card) facing down, gently slide the SIM card into the slot.
3. Check whether the SIM card slot is damaged. Try to clean the black spots on the SIM card with alcohol. If the black spots cannot be cleaned in the end, may be the spot is broken.
4. Try another SIM card.
5. If still not work, send an email to support@cudy.com. Please include below information:
(1) A photo of circuit side of the SIM card.
(2) The result of when you try another SIM card.
(3) Go to Diagnostic Tools->GO->Download and save the bin file.
(4) Other information you thinks is important.