Hi you should not lose your data. It is always recommended before you do any plugin changes -updates or upgrades, you should always do a backup of your website, just in case something doesn't go right. We do that all the time just to cover ourselves and save hours of fixing things. I see you have the MBT3 Pro Upgrade just do the following.
Step 1 Upload your upgraded MBT to your plugins sure you have the original - when you purchased the upgrade you were able to get a zipped file of that. See screenshot for uploading
Once you do that it will show up in your installed plugins list.
Step 2 Make sure you keep the original MBT (the not upgrade version) activated and activate the latest plugin upgrade. Make sure the old versions are deactivated. There should only be the 2 activated.
Step 3 Once you do that go to the original plugin (first arrow in this example)
Go to Settings and add your new license key for the new upgrade, then all the new features should be available.