Hi, and welcome!
Please see the FAQ: What's a reproducible example (`reprex`) and how do I create one? Using a reprex, complete with representative data will attract quicker and more answers.
Some coding questions are simple enough not to require them. This one, however, is missing the library() calls and the data objects, making it time consuming to reproduce.
The best I can offer is to compare the PROJ of the base and newdata objects:
gstat object and newdata have different coordinate reference systems.