Assign License and Permission set
If you are using User based licensing app, you should assign License to the user manually.
The first step before assigning License is to modify the permission set.
With the package installation, you will get two permission sets
Edit Permission Set:
Salesforce > Setup > Manage Users > Permission set > Choose ValueText User to edit.
Repeat the same step for below objects
We can optionally skip but give access for SMS Outbox and SMS Inbox.
Perform the same process for “ValueText User (Template Editor). This Permission Set will act like Admin for the app and provides access to all SMS objects.
If you are using License based version, then you should assign the License manually. In addition to assigning the Permission Set to the User, License should also be assigned to give the access to the User for the App.
Salesforce > Setup > Installed packages > right side of ValueText you will find manage License > click on it
Now select the User and assign the License.
Important Note: User should have Permission Set assigned along with License to use the app.