Hi @Anand Indupally, and welcome.
To get participant data to pass across. First make sure you are Setting the Participant Data AFTER the variable is created and updated. If you only set it at the start, but then the variable updates later in the flow, that isn't carried over automatically.
Eg
Then in your receiving flow make sure the Get Participant Data key matches exactly what the previous flow was.

When testing can be good to use a play audio to make sure the value was read successfully.
You can also check the conversation detail in the interaction UI or through the API to confirm the data was written to the participant correctly.
If you instead mean after the call is answered, ie agent then updates variables and that isn't being updated in the participant data when transferring to a flow, let us know, that is again doable but requires a few extra steps.
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Anton Vroon
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