# EM7455 "System mode: Unknown" Issue

**URL:** <https://forum.sierrawireless.com/t/em7455-system-mode-unknown-issue/21337>\
**Category:** IoT Modules\
**Created:** [August 27, 2020, 11:15pm UTC](https://forum.sierrawireless.com/t/em7455-system-mode-unknown-issue/21337 "2020-08-27T23:15:04Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![Donald](https://avatars.discourse-cdn.com/v4/letter/d/ac8455/32.png) [@Donald](https://forum.sierrawireless.com/u/Donald)\
**Post date:** [August 31, 2020, 3:12am UTC](https://forum.sierrawireless.com/t/em7455-system-mode-unknown-issue/21337/4 "2020-08-31T03:12:04Z")

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Hi @akn

I see your EM7455 registered network successfully on previous tickets.  
[https://forum.sierrawireless.com/t/automatic-rrc-connection-request/20071/5](https://forum.sierrawireless.com/t/automatic-rrc-connection-request/20071/5)

> [@Verizon SIM with static IP on EM7455](https://forum.sierrawireless.com/t/verizon-sim-with-static-ip-on-em7455/21205/5):
>
> It is a 4G SIM. All the 3G and 4G bands were enabled in current modem setting. With the Verizon Static SIM, it was always trying 3G only bands and going into deep sleep mode. Due to this I misinterpreted it as 3G SIM. It worked after selecting LTE only networks AT!SELRAT=06 or AT!BAND=9

Do you use the same Verizon SIM?

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