Question about VOIP Provider

Hello World.
I have a SIP Trunk configured in my asterisk, for example if i dial a number and an IVR answer the call and i press on options of the IVR System, anything happen, is like the SIP Trunk dont detect i’m pressing an option.

I have done this for example:
Call 1800-000-0000 --> Thanks for call to BLA BLA BLA --> For Sales press 1, for support press 2
When i press 1 in the phone, anything happen, but this just happen to my using the SIP TRUNK, if i dial using my normal Land line, and press 1 using my analog phone, i can hear the other options…

What i hape to configure in my sip trunk, Have ever happen to you this situation? How to fix it?

Hi

RTFM but the clue is to set the dtmfmode correctly in the sip.conf

Ian