Fail to convert

[rogelioamancisidor]

I have clone the repo and paste my QTI 1.2 .xml file with a bunch of questions in the folder ./assessment/orig/questions.xml. Then I run bash example_run.sh which contains the following script

#!/bin/bash
./migrate.py --ucvars --nogui --overwrite --cpout=assessments/out/ assessments/orig/

Then I get 3 files in ./assessment/out/: assessmentItems, assessmentTests, and the imsmanifest.xml. I compress the outfolder, i.e. the 3 folders/file mentioned previously, and upload it into a course management system (itslearning). However, I get the following error message

Issue: Invalid node.
The 'http://www.imsglobal.org/xsd/imsqti_v2p1:qtiMetadata' element is not declared. 
File: imsmanifest.xml
Position (line, character): 1, 961

Any idea what is wrong?