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Why the Y direction of “Error to GCP Initial Position” is large?

I have 14 valid GCPs in a project with 732 images,coveing about 13.9km2 with an average GSD of  9.69 cm / 3.82 in. All of GCPs is survey by RTK GNSS instrument and GCPs has fixed-solution. But the Y direction  of “Error to GCP Initial Position” is lagre,The error is about 4m,  Quality Report indicate that the project is georeferenced.

I’ve read the support article: https://support.pix4d.com/hc/en-us/articles/202969759-Can-the-Theoretical-Error-S-X-Y-Z-of-a-GCP-be-small-while-the-Error-to-GCP-Initial-Position-is-high-#gsc.tab=0

What am I doing wrong?

Below is the quality report link.
https://pan.baidu.com/s/1vh3UaTRgMM5UDsrA_wCyMA 

Hello Li,

with which version of the software has the project been created? And with which software version are you reopening the project?
Can you see the shift also in the rayCloud?

If you click Process > Reoptimize , is the issue solved?

Alice