SOLVED: ICCID empty using 1NCE

Hi, I'm using a Holgram SIM and can get both IMEI and ICCID with GSMModem's methods (even if getICCID is not documented on the refernce library). The same code but using a 1NCE SIM returns IMEI correctly bur ICCID string seems to be empty. Does anyone experience the same problem? Thanks for any advice.

Here is the snippet just for reference:

...
GSMModem gsm_modem;
...
char imei[GSM_IMEI_SIZE] = ""; // 15 + 1
char iccid[GSM_ICCID_SIZE] = ""; // 19 + 1
...
gsm_modem.begin(); // assuming no errors
gsm_modem.getIMEI().toCharArray(imei, 16);
Serial.println(imei); // prints actual IMEI
gsm_modem.getICCID().toCharArray(iccid, 20);
Serial.println(iccid); // empty with 1NCE SIM, actual ICCID with Hologram SIM
...

Also tried with a Swisscom SIM, same problem, so I suppose it is not related to 1NCE but to the library. Adding a "small" delay (e.g. 100ms) between the two calls (IMEI and ICCID) the ICCID can finally be read on all SIMs (Hologram, 1NCE and Swisscom) :man_facepalming: