Versent (Australia) interview questions

Phone call and face to face..two people panel..then hiring manager interview. It was straightforward..they people seemed nice..remote working opportunity as well. Not sure what to include as I now have to write up to 30 words ..phew

I had a 1.5-hour in-person interview that included a mix of behavioral and technical questions (discussing previous work experience, technologies used, Agile methodology, debugging techniques), followed by a simple 15-minute coding test where help was offered if needed. The interviewers were very friendly and supportive throughout. Up to this point, I would give the experience a rating of over 4.5 out of 5. However, after completing a take-home code challenge which involved designing a public API, I received an email from their team lead accusing me of using AI assistance for the task without any evidence. The job description did not explicitly prohibit the use of any tools, and I was unaware that using something like ChatGPT was not allowed. They rejected me solely based on the concern that I might have used GPT, which "raised too many concerns for them"(Original message in Email). This decision is incomprehensible to me. I am confident that their team (and any competent developer) would leverage AI tools to enhance efficiency and support their development and testing processes, rather than relying on AI.