The Verification request was received and is still pending completion.
This can happen when:
A Verification Check is performed on a Verification that is still in progress.
A Verification was created for a phone number whose carrier is not supported for the selected Twilio Region. For example, if an SNA Verification was created for a UK phone number using the US1 Region instead of the IE1 Region. In this case, the Verification request will never complete.
Possible Solutions
Confirm the Verification Check is performed only after a HTTP 200 Response is received from invoking the SNA URL.
Retry if the Verification is still in its validity window and has not expired.
Confirm the Verification was created in the correct Twilio Region for the phone number, see
Using Verify Silent Network Auth with Twilio Regions
for more detailed information. If it was not, retry Verification using correct Region.