There have been similar issues asked many times in the past.

Some cellular operators dispatch to customers cellular SIM cards that do not have phone number information returned when being queried by standard phone firmware, while the phone hardware can get the phone number to make cellular connection possible.  For such cases, the only way to solve problem is to request the cellular operator to replace such SIM cards with others that have phone number information written for phone firmware query.

ICCID of the SIM card and IMEI number of the phone should always be readable by the firmware, and Soti device agent can get such information to be shown on your MobiControl web-console.  I am not sure if there are any recent changes for some Android 10+ phones due to app permission of the device agent  or MDM/EMM enrollment mode of the devices.  I could not rule out possibilities that end-user can disallow permission of the device agent to get some permissions, especially those related to privacy, on some new device running new Android 10+ firmware.  For some newer device firmware version, Goolge might also have explicitly disallow some privacy related information to be read out by MDM/EMM software for devices enrolled in BYOD mode.

So, it is likely that there is nothing you can do remotely on your MobiControl web-console.