Interpolation between different grids

[zxcdsaqwe8]

I established two grids in the same geometric region, but when I interpolated the quantities on one grid to the other, it would report an error. May I ask how this problem can be solved? When I use the projection directly, it won't report an error, but I don't know if it's appropriate to do so?

[dham]

There isn't really enough information here to help you. Please provide a minimal failing example.