EY Assurance Associate interview questions

I interviewed at EY GDS, their hiring process is strange, They have done Interview as virtually due to covid, after interview they scheduled to do assessment, but I received offer letter before attempting assessment, after 3 days recruiters informed me that I failed in assessment, the reason for receiving offer letter was system error. This is the worst experience I had with EY GDS India. How can reputed company will do this mistake, I never heard such type of scenarios.