mrlayance – welcome to the forum.
Your DigitMap looks ok if this is true:
Physical Interfaces > PHONE Port > PrimaryLine: PSTN Line
I'm assuming that you wish to dial seven digits then have OBi prepend 902 and then send 902xxxxxxx out to POTS.
Try this test: Press "#" which should give you POTS dial tone, then dial 902xxxxxxx. If this works we know your POTS line is working correctly.
Go to your local OBi web page (dial ***1 for local IP address), look in Status > Call History. This will show digits dialled from PHONE1 and digits sent out to LINE1 (POTS). If all that looks ok, then it might point to a timing problem with the OBi seizing the POTS line then sending the digits out.