I assumed you dialed  the number correctly? Also, could you add +1 and area code before calling the number?

Yes, the number was dialled correctly.  1+ included.  It is a mystery.  Can connect on Shaw landline.  Talked with someone at Koodo and even she got the same “6UC2” code….not in service, when she tried.  Sister is looking into it from a Telus store and they still can’t figure out what is happening.  

Did she restart her phone after porting over? What about removing her SIM card and inserting it in another device to see if it works?

It was only Koodo customers  that received the not in service recording.  Any other people with different carriers had no trouble.  Just Koodo to Telus calls.  Anyway thanks to my sister, who could actually go to a Telus store, and get them to finally work some magic somewhere, it is now working,  but we are uneasy with Telus because my rural living mother is 86 and she had nothing but trouble over the last year with Telus landline, so she decided to drop the landline and go solely with cell using her landline number.  That’s when this all started.  Telus has been a frustrating disappointment.  Just my opinion.