XYZ Power Platform Developer interview questions

I was reached up by a phone call (10 th dec 2024) and was asked to complete an online assignment within one day . After completing the assignment ( develop an app) they conducted an online interview over the assignment . It took one week for Hr to give back the Feed back that i was appointed for trainee post and it was discussed that the offer letter would be released by 1st week on jan 2025 . However there was email or call even after the 1st week . When tried to enquire for the offer letter they replied that there was no such empty position for the role of Power platform developer . Very unprofessional way of conducting interview process , better don't waste time on such unprofessional small startups .