Hi @Michiel Vlieger (student),
I'm glad to hear that your issue has been resolved. And thanks for sharing the solution, which might be beneficial to other community members reading this thread. Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others ", I'll repost your solution in case you'd like to accept the answer.
Question: How to fix product recognition custom model stuck on training?
Answer: The problem is fixed itself! After training for 24 hours it succeeded.
If you encounter any issues in the future, don't hesitate to reach out to the community forum for assistance. Thank you.
Do not forget to click Accept Answer
and Yes
for was this answer helpful.