DTMF timeout delay

[bazzacad]

Phones: Yealink T42G & T48G
Sometimes our receptionist will hit *2 to do an attend transfer, then look at her cheat sheet to look up the person's extension (yes, she should look it up first). She has about 3 seconds to enter the extension, if not the operation times out & it says that's no a valid extension. Is there a setting somewhere to increase this timeout/delay period?

[Yealink_Jim]

Hi,
You can use the following to prolong operation time

[bazzacad]

I've changed these settings & it has no effect.
I hit *2, hear the dial tone, count to 3-4 & hear "Sorry not a valid extension"