Please help us help you and fill where relevant:
Your LimeSurvey version:   LimeSurvey Community Edition       Version 6.0.3+230424   
Own server or LimeSurvey hosting: Own Server
Survey theme/template: Fruit
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Dear Experts,

With help from Joffm and Denis, I successfully tested the survey I need in my test machine limesurvey.local without any problems. Now I moved the survey to our production machine, both are running Ubuntu 20.04. I imported the survey, preview it, all are normal. But after I activated the survey and simply click Run survey, it showed me "Sorry you did not use a valid URL", I added the Newtest=Y seems unhelpful.
limesurvey.XXXX.edu.cn/limesurvey/index....2.rachel10@apple.com

Any ideas? I must have missed some important changes to import it to another system?
I'm attaching my imported lss files (I tested both but to no avail)
 

No need for assistance now, sorry about this! I forgot to install and activate the stat plugin in my production server and everything seems fine now.

Thanks for reading.