To use TXTinIT app you must assign licenses to authorised users.
This guide will show you how to do so. Note that TXTinIT Free comes with 1 user license.
Assign TXTinIT Licenses
Step 1: Look For The TXTinIT Package
Go to Setup.
Search for Installed Packages.
Click on it.
Step 2: Click On Manage Licenses
Look for the TXTinIT Installed Package and click Manage Licenses.
You do not need this step if you have purchased a Site License.
Step 3: Click On Add Users
Click on the Add Users button.
Step 4: Assign Licenses to Users
Look for the Users that require licenses.
Click on the tick box.
When all Users have been selected, click on Add.