I am having some issues getting the 6 GHz band to connect to my desktop PC. It works fine on every other compatible device we have in the house (iPhone 15 Pro, Samsung Galaxy, MacBook, ThinkPads). I had Claude help me troubleshoot beyond the basics (reinstall WiFi card + drivers, update firmware on adapter and router), but I am still unable to figure this out. See below for details.

Setup:
    ∙    Adapter: TP-Link Archer TBE550E (driver v5.4.0.3119, dated July 2025)
    ∙    Router: TP-Link Deco BE68 (latest firmware)
    ∙    OS: Windows 11 64-bit
    ∙    Motherboard: Gigabyte X570 Aorus Elite

Problem:
The TBE550E can see multiple 6 GHz BSSIDs from the Deco BE68 at strong signal strength (69–82%) on channel 69, 802.11be with H2E and MLD supported. However, the adapter will not associate on 6 GHz under any configuration. 2.4 GHz and 5 GHz connect and work normally.
Additionally, when connected to the MLO SSID, netsh wlan show interfaces confirms only 2.4 GHz and 5 GHz links are active — 6 GHz is never utilized as an MLO link despite being visible.
Already verified/tested:
    ∙    WPA3 enabled
    ∙    Channel width set to 80, 160, and 320 MHz — all fail
    ∙    Forced 6 GHz via Deco app per-device band preference — fails to connect
    ∙    Forced 6 GHz via adapter Advanced settings in Windows Device Manager — fails to connect
    ∙    Non-MLO SSID also fails to connect on 6 GHz using the same checks as above
    ∙    netsh wlan show drivers confirms 3 bands supported including 6 GHz (5955–7115 MHz)
    ∙    netsh wlan show networks confirms 6 GHz BSSIDs are visible with good signal

Request:
Is there a known fix or planned firmware/driver update to resolve 6 GHz association between the TBE550E and Deco BE68?