Replacing flash with DTMF

I’m using asterisk with webrtc in chrome and also using a gateway. My problem is that I can’t send the hook-flash signal to asterisk for some reason. Is there a possibility to trigger hook flash by sending DTMF signals ? (which apparently work for me )
Example: I want to trigger the standard hold functionality by sending the following DTMF sequence: #123.
With regards,

As a workaround can I hold a channel using AMI or AGI as a workaround ?

To hold a SIP channel you must send SDP with a=sendonly, or a=inactive, or with c= with SIP does not use hook flash for its own purposes, although may be able forward it through to the remote system.

Please use Asterisk Support for support questions.

If you want register recall, rather than hold, you can use features.conf settings, or you can use native SIP transfers.