Is there a way to flash the radio firmware on a doogee BL12000, so that it will get 4G, and 4G LTE in the usa on T-mobile network

The phone appears to be compatible with all bandwidths up to the 4G network. If your sim is up to date with your network coverage, it should all work. Check this product review to determine if this info is correct and maybe check with your service provider that the networks are compatible so you don't end up with a phone that is a paperweight.
Doogee BL9000 Smartphone Review

I found this on my search for you, hopefully it'll help -

Doogee S60 All in One Thread Firmware Recovery ROOT Xposed

hi margaret.
see if this link helps you out.
How do set the alarm on my Doogee X5 MAX mobile phone Google Search

If the phone can use 4G it will do it automatically, no setting change is needed.

It should work in the U.S. as it is a 4G LTE phone..just remember to manually enter APN settings for your network provider.

Eruck
Boost only allows certain serial numbers on their network. They don't let non Boost phones on network.

Mark
Motorola Support

You can't flash a CDMA phone(HTC EVO 4G LTE on Sprint(CDMA network) to a GSM network(Straight talk which is on T-Mobile's network(GSM network) the hardware is not interchangeable. A GSM SIM card is not the same as a 4G LTE SIM card(UUID) they store different data. GSM SIM hold your carrier account information that authorizes you to use the network while a UUID only hold data that is relevant to you accessing the 4G LTE part of the network the remainder of your carrier data is stored on the phone hardware.

You may need to upgrade to a newer sim card. There have been changes recently, esp. with the broader adoption of, and newer versions of LTE. LTE is a whole different radio system than 3g or even 4g. (It is actually 3g on super steroids) I think a sim upgrade should fix the problem.

You can get the subsidy unlock code for your Motorola Atrix HD LTE by visiting the site Prounlocking.com .Here,they ask to provide the model,country,network provider name and IMEI number of your mobile.After they deliver the unlock code for your Motorola Atrix HD LTE cellular phone through mail.After unlocking it ,you can use any GSM network on your mobile.

From the installation guide for this AP, I find the following:

LED Indicators

The unit has LED activity indicators on the front of the case provide a status display indicating error conditions, transmission, and network activity for the 802.11a (amber) radio or the 802.11b/g (green) radio.

802.11a Activity LED Amber

The amber LED flashes three times per second until firmware is loaded. During boot, 802.11a mobiles cannot associate. After adoption, the amber LED is steady or flashes with 802.11a radio traffic.

The amber LED flashes once per second if an error prevents the 802.11a radio from operating normally.

802.11b/g Activity LED Green

The green LED flashes three times per second until firmware is loaded. During boot, 802.11b/g mobiles cannot associate. After adoption, the green LED is steady or flashes with 802.11b/g radio traffic.

The green LED flashes once per second if an error prevents the 802.11b/g radio from operating normally.

From this, it appears that the 802.11A radio is malfunctioning.

Here is the Motorola support web page for this device.