Which tests did you do?
Are you having troubles with TIM sim cards? Or with all the operators?
- Are the antennas connected to the device?
- Is the Sim card able to reach internet connections?
- Did you installed the Sim card in the right way?
Please take a look to this start guide. --> https://wiki.teltonika-networks.com/view/RUT230_First_Start
Also, your RUT230 is able to reach only 3G or lower connections, has your operator this kind of frequencies in your place?
I'll be waiting forward to your feedback.