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The R11e-LTE6 https://mikrotik.com/product/r11e_lte6 have
2G Category Class12
2G bands 2 (1900MHz) / 3 (1800MHz) / 5 (850MHz) / 8 (900MHz)
3G Category R7 (21Mbps Downlinks, 5.76Mbps Uplink) / R8 (42.2Mbps Downlink, 5.76Mbps Uplink)
3G bands 1 (2100MHz) / 2 (1900MHz) / 5 (850MHz) / 8 (900MHz)
LTE Category 6 (300Mbit/s Downlink, 50Mbit/s Uplink)
LTE FDD bands 1 (2100MHz) / 2 (1900MHz) / > 3 (1800MHz) > / 7 (2600MHz) / 8 (900 MHz) / 20 (800MHz) / 5 (850MHz) / 12 (700MHz) / 17 (700MHz) / 25 (1900MHz) / 26 (850MHz)
LTE TDD bands 38 (2600MHz) / > 40 (2300MHz) > / 39 (1900MHz) / 41n (2500MHz)
Band 5 is only at 2G, not at LTE.
You can read about lte at https://wiki.mikrotik.com/wiki/Manual:Interface/LTE
Enable LTE logs by: /system logging add topics=lte
Create a watchdog Logger for LTE: http://forum.mikrotik.com/t/r11e-lte6-2ca-not-staying-connected/136004/22