Whenever you connect your iPhone or iPad to a computer for the first time, a message asks whether you ‘Trust This Computer?’.
Trusted computers can sync with your iOS device and let you access your iPhone’s photos, videos, contacts, messages etc., on your computer. These computers remain trusted unless you change the privacy settings for the trusted computers on your iPhone.
If you choose not to trust a computer, you block the access of your iPhone data on it and thus receive the trust alert every time you connect your iPhone to that computer.
Therefore, whenever you get a trust alert, you can do either of the two things:
Now, launch Stellar Data Recovery for iPhone software on your computer to recover the lost iPhone data.