Login to your Salesforce org where the package is installed.
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FIND {0} IN ALL FIELDS RETURNING Contact(Name, Id ORDER BY LASTMODIFIEDDATE DESC LIMIT 1) LIMIT 10
(Change Object Name in Query as per requirement)
Now, Go to Custom Settings and Click on Manage of “Features Entitlement“.
Mark the checkbox true for SMS and eFax.
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Now Go to Object Settings and Provide Access (Read, Create) to below objects:
Contact
SMS Messages
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Enter the details as shown in below picture.
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Click Save.
Congratulations! You have successfully installed the Application.