Twilio / T-Mobile SIM with RAK7258 gives QMUXError = 0xe

We are using a Twilio SIM with the RAK7258. The SIM uses T-Mobile carrier service here in the USA. When we enable LTE, it connects briefly and then disconnects, repeatedly. In the system log it shows:

Wed Dec 18 20:01:04 2019 kern.info quectel-CM[16868]: requestRegistrationState2 MCC: 310, MNC: 260, PS: Attached, DataCap: LTE
Wed Dec 18 20:01:04 2019 kern.info quectel-CM[16868]: requestSetupDataCall QMUXResult = 0x1, QMUXError = 0xe
Wed Dec 18 20:01:09 2019 kern.info quectel-CM[16868]: requestRegistrationState2 MCC: 310, MNC: 260, PS: Attached, DataCap: LTE
Wed Dec 18 20:01:09 2019 kern.info quectel-CM[16868]: requestSetupDataCall QMUXResult = 0x1, QMUXError = 0xe

The SIM works fine in other equipment. Also a different SIM (from our local AT&T mobile carrier) works fine in the RAK7258. Any ideas on why the Twilio/T-Mobile SIM is not working, or what we could try to fix it?

We have also now tried an official T-Mobile SIM, but get the same errors. It appears that the RAK7258 does not work on the T-Mobile network at all.

Can you confirm that APN name and PIN are set correctly?
If No PIN and already tried with APN name, please try leaving APN field blank.

Yes, the APN is set correctly and there is no PIN for this SIM (confirmed both). I tried leaving the APN field blank but the error message does not change. Same problem.

I am also in contact with Twilio to see if they can provide any information on the error message. Their support person asked if you could identify which of the four models of Quectel EG95 listed here is used in the RAK7258: https://www.quectel.com/product/eg95.htm

Thanks!

Asking this question again because we have not received a response and are running low on time in our evaluation of your equipment for use in our network.

Can you please confirm which specific model of Quectel EG95 is used in the RAK7258?

Hi @faludi. Sorry for late replay :frowning: . For USA, EG95-NA is used.
Please feel free to contact me at [email protected] for future assistans on this.

Best regards.