I don't think there is IMEI number available for 2G-IOT since for now the product is development board instead of cellphone. The IMEI number need to apply from government.
You can adjust the IMEi Number on the modem "factory partition" with the Command AT +EGMR
AT +ÉGMR=2,7 reads the actuell value from modem
AT +EGMR=1,7,"123456789012345" write the new value in the memory (remove 123456789012345 with your IMEI)
███ Greatings from Germany ███
███ Reinhard ███
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I changed the imei number with minicom in the ubuntu system, but the gsm module did not work. When you restart the system, the imei number is 0000 .... 00 again.
IMEIs are not longer assigned by governments. OrangePI needs to register here in order to get assigned an IMEI prefix. https://imeidb.gsma.com/imei/index#