Our apologies for the late response and thank you for your inquiry.
This is how e-SIM functionality should work as described below:
GPRS settings and Roaming Operators can be configured separately for SIM (SIM1) and for eSIM (SIM2).
In SIM2 Roaming/ Home operator list home operator must be added to any part of the list that functionality works correctly.
Dual SIM operator search functionality works like that: SIM1 and SIM2 home operators have the highest priority: When the device is connected to the home operator - the manual roaming operator search is disabled.
When the device is disconnected from the home operator - the operator search procedure is initiated as normal every 15 minutes. SIM1 Roaming operators list has higher priority then SIM2 Roaming Operator list.
When the device finds a new operator from SIM1/SIM2 lists – it switches to new SIM according to the list and connects to the new operator.
Please check FMB001 user manual for the working algorithm. This information you can find on the link: https://wiki.teltonika-gps.com/view/FMB120_GSM_Operators_settings
Also, please let us know if you will need any help or you will have questions.