AutoThrottle not activating

[Evogaming2000]

Aircraft Version

Development

Build info

{
    "package_version": "0.1.15-5",
    "fms_man_version": "HD-P000-1-15-5",
    "fms_bak_version": "HD-C000-1-15-5"
}

Describe the bug

Every time i press the A/T button it flashes for a split second then turned off, this is while AP is engaged and VNAV/LNAV is on, this means that the autopilot is not controlling the throttle of the aircraft to the correct speed and i still have full manual control overthrottle

Expected behavior

Once A/T button is pressed it should remain illuminated until autothrottle is disengaged. A/T should then take full control over the throttle to work in conjunction with the AP and the speeds set in FMC.

Steps to reproduce

Set up aircract setting a route and doing everything needed in the FMC
set autothrottle on
Take off
Autopilot on
LNAV/VNAV on

References (optional)

https://gyazo.com/14d87ea7ef7f27387f9a54519a3bde60

Additional info (optional)

No response

Discord Username (optional)

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