Huawei E3531 doesn't work on RB2011UiAS

On 2 units same issue, with both 6.40.6 and 6.41.3 RouterOS versions.
The USB modem Huawei E3531 is detected when connected, but no usb ports are available.

This is the output on console:

/system resource usb print detail 
 0 device="1-0" vendor="Linux 3.3.5 ehci_hcd" name="RB400 EHCI" serial-number="rb400_usb" vendor-id="0x1d6b" 
   device-id="0x0002" speed="480" ports=1 usb-version=" 2.00" 
1 device="1-1" vendor="HUAWEI" name="HUAWEI Mobile" serial-number="FFFFFFFFFFFFFFFF"
   vendor-id="0x12d1" device-id="0x1f01" speed="480" usb-version=" 2.00"

/port print    
Flags: I - inactive 
 #   DEVICE NAME                                      CHANNELS USED-BY                                   BAUD-RATE
 0          serial0                                          1 Serial Console                            auto

I bought 5 pieces of this particular Huawei model because it is reported as “supported” on https://wiki.mikrotik.com/wiki/Manual:Peripherals :frowning:

Any advice?

might feel like a little alchemy, but try to add some external usb power to it. had similar issues with a huawei stick (can’ remember the type), which worked just fine with the same routeros version on a hap ac lite for no apparent reason.