Problem detecting the SIM card via nrf connect


I'm trying to add another LTE device to nrf connect. But I am facing problem when adding it, I have my own sim card for iot from Singtel, It worked with the first card, but with the other one it seems to be a little bit buggy... Instead of having led 3 and 4 blinking at the same time, i have only led 4 on (without blinking). I even tried the pairing procedure but it was not working...

Please Nordic, what should I do?