T41 not updating

[troosters]

Hello,
I have connected 2 t41's to a Session Border Controller to a 3cx server.
The firmware on the phones now is 36.71.0.40, but when I try to update it to 9.71.0.224 it starts updating, but it does not update at all ??
I do this via the webinterface of the phone.

[Yealink Support]

Hi troosters,

The firmware 9.71.0.224 belongs to T20. So you can't use this firmware to upgrade the T41.
I will supply two firmware to you. You can choose one and download it to upgrade you phone.

36.72.0.25(the latest neutral version)

3671.0.224 (Supported by 3CX Phone System)

thanks