The Join Now option might not appear in the meeting notification if the meeting organizer isn't using a BlackBerry smartphone that supports the Join Now feature or if the meeting organizer didn't enter the conference call information correctly. You might need to change your smart dialing options so that you can enter the conference call using the Join Now option.
Try the following actions:
key >
Options >
Smart
Dialing. In the To access extensions in all other corporations section, change the Wait For field to the highest value or to My Response if your BlackBerry smartphone is connected to a CDMA network. Try entering the conference call with the Join Now option again.