Data displayed in the Terminal frame often lose content.
There have been many discussions on this forum over the years about the behaviour of the terminal widget.
Many issues have been resolved by an update to the app, or a different approach to the code being used.
I’d suggest that you start by searching the forum for other posts and see if any of the issues reflect what you’re experiencing, and whether any of the solutions work for you.
If you still have the problem then I’d suggest that you make a propert post that explains which app O/S and version you’re using, which Blynk library version you have, and post some simplified code that successfully re-creates the issue, along with a description of how to replicate the issue.
Something like this thread is what is needed for the developers to replicate the issue and resolve it:
Pete.