You have a bit of an up-hill challenge here. There is not an easy way to look for that phone number in the callbacks within the Architect. You will need a data action to the GC API to pull all the callback conversations in the queue then parse the collection retrieved for the phone number and then use Architect decisions and logic.
This might be beyond your current level at this point, but there are several examples in the Architect resource and the developer sites. It is doable, but will require that data action and parsing functions.
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Robert Wakefield-Carl
Avtex Solutions, LLC
Contact Center Innovation Architect
robertwc@avtex.comhttps://www.Avtex.comhttps://RobertWC.Blogspot.com------------------------------