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In Wise Owl, this can sometimes happen when you create a new contact and then immediately try to create a new matter with that contact.
Your browser goes into the New Matter screen and because that location is 'cached' (remembered) on your browser, it doesn't look for new data (aka your new contact).
One option (if you have the time) is to allow the browser time to catch up or re-look for a new version of the page. This will take time and that will vary per computer and it's specifications and per browser.
ALTERNATIVELY
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