I tried using the "GL.iNet GL-E750V2 (MUDI)" with a 4G SIM and roaming activated, but the connection was unsuccessful.
From what I saw, the roaming was enabled on the GL-E750V2, but I still encountered an error:
Tue Jan 28 18:05:21 2025 daemon.notice netifd: radio1 (4223): sh: acs_survey: out of range
Tue Jan 28 18:05:21 2025 daemon.notice netifd: modem_1_1_2 (4220):
Tue Jan 28 18:05:21 2025 daemon.notice netifd: modem_1_1_2 (4220): AT+QNWPREFCFG="roam_pref",255
Tue Jan 28 18:05:21 2025 daemon.notice netifd: modem_1_1_2 (4220): OK
Tue Jan 28 18:05:22 2025 daemon.notice netifd: radio1 (4223): sh: acs_survey: out of range
Tue Jan 28 18:05:22 2025 daemon.err lua: (...6e/ipkg-mips_24kc/gl-sdk4-repeater/usr/sbin/repeater:385) Wait phy ready...
Tue Jan 28 18:05:23 2025 daemon.notice netifd: modem_1_1_2 (4220):
Tue Jan 28 18:05:23 2025 daemon.notice netifd: modem_1_1_2 (4220): AT+QNWCFG="data_roaming",0
Tue Jan 28 18:05:23 2025 daemon.notice netifd: modem_1_1_2 (4220): ERROR
Tue Jan 28 18:05:23 2025 user.notice mwan3[4218]: Using firewall mask 0x3F00
Tue Jan 28 18:05:23 2025 daemon.notice ovpnclient[4449]: OpenVPN 2.5.7 mips-openwrt-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [MH/PKTINFO] [AEAD]
Tue Jan 28 18:05:23 2025 daemon.notice ovpnclient[4449]: library versions: OpenSSL 1.1.1t 7 Feb 2023, LZO 2.10
Tue Jan 28 18:05:23 2025 daemon.warn ovpnclient[4449]: WARNING: --ns-cert-type is DEPRECATED. Use --remote-cert-tls instead.
Tue Jan 28 18:05:23 2025 daemon.warn ovpnclient[4449]: NOTE: the current --script-security setting may allow this configuration to call user-defined scripts
Tue Jan 28 18:05:23 2025 daemon.notice ovpnclient[4449]: Outgoing Control Channel Authentication: Using 512 bit message hash 'SHA512' for HMAC authentication
Tue Jan 28 18:05:23 2025 daemon.notice ovpnclient[4449]: Incoming Control Channel Authentication: Using 512 bit message hash 'SHA512' for HMAC authentication
Tue Jan 28 18:05:23 2025 daemon.notice netifd: modem_1_1_2 (4220):
Tue Jan 28 18:05:23 2025 daemon.notice netifd: modem_1_1_2 (4220): AT+QCFG="roamservice",255
Tue Jan 28 18:05:23 2025 daemon.notice netifd: modem_1_1_2 (4220): ERROR
Tue Jan 28 18:05:23 2025 user.notice mwan3[4218]: Max interface count is 60
Tue Jan 28 18:05:23 2025 daemon.err lua: (...6e/ipkg-mips_24kc/gl-sdk4-repeater/usr/sbin/repeater:385) Wait phy ready...
Tue Jan 28 18:05:24 2025 daemon.notice netifd: modem_1_1_2 (4220): Failed to parse message data
Tue Jan 28 18:05:24 2025 daemon.err lua: (...6e/ipkg-mips_24kc/gl-sdk4-repeater/usr/sbin/repeater:385) Wait phy ready...
Tue Jan 28 18:05:25 2025 daemon.notice netifd: modem_1_1_2 (4220):
Tue Jan 28 18:05:25 2025 daemon.notice netifd: modem_1_1_2 (4220): AT+QNWPREFCFG="mode_pref",LTE
Tue Jan 28 18:05:25 2025 daemon.notice netifd: modem_1_1_2 (4220): OK
Tue Jan 28 18:05:25 2025 daemon.notice hostapd: Configuration file: /var/run/hostapd-phy0.conf (phy wlan1) --> new PHY
Tue Jan 28 18:05:25 2025 daemon.err lua: (...6e/ipkg-mips_24kc/gl-sdk4-repeater/usr/sbin/repeater:385) Wait phy ready...
Tue Jan 28 18:05:27 2025 kern.err kernel: [ 123.231002] ath10k_pci 0000:00:00.0: failed to read device EEPROM at 0000
Tue Jan 28 18:05:27 2025 kern.warn kernel: [ 123.231027] ath10k_pci 0000:00:00.0: failed to read calibration data from EEPROM: -22
Tue Jan 28 18:05:27 2025 daemon.err lua: (...6e/ipkg-mips_24kc/gl-sdk4-repeater/usr/sbin/repeater:385) Wait phy ready...
Tue Jan 28 18:05:27 2025 daemon.notice netifd: modem_1_1_2 (4220):
Tue Jan 28 18:05:27 2025 daemon.notice netifd: modem_1_1_2 (4220): AT+QNWPREFCFG="lte_band",1:2:3:4:5:7:8:12:13:14:17:18:19:20:25:26:28:29:30:32:34:38:39:40:41:42:43:46:48:66:71
Tue Jan 28 18:05:27 2025 daemon.notice netifd: modem_1_1_2 (4220): OK
Tue Jan 28 18:05:27 2025 daemon.notice netifd: modem_1_1_2 (4220):
Tue Jan 28 18:05:27 2025 daemon.notice netifd: modem_1_1_2 (4220): AT+QCFG="band",0,420000a7e2bb0f38df
Tue Jan 28 18:05:27 2025 daemon.notice netifd: modem_1_1_2 (4220): ERROR
