Autofill lookup field based on internet input

I have a Customer Service application that is open to the public. One of the input fields is used to enter a Bill of Lading number. I have that app connected to the main app that I use to adjudicate claims. After the customer enters a request, I have to manually enter that Bill of Lading number into a lookup field which then links that request to the main app that houses their claim. Is there any way to get the app to use the Bill of Lading number the customer enters to automatically fill in the lookup field as well?

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Rhonda Rhonda
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