Barclays interview questions

Applied for the role and was sent an email saying "We now invite you to our Experience Platform to complete your assessment." I tried to research what this entailed and assumed it meant the numerical and verbal tests etc, however, it was a personality sort of test. Therefore, no information on the sort of test at all and therefore all of the prep I had done was wrong. There was no POC for feedback or questions and a generic email with no specific justification as to why I was rejected, along with the line "Replies to this message are undeliverable and will not reach the Resourcing Team. Please do not reply."

There were 4 rounds . 1 general discussion, 1 technical, 1 managers round and 1 HR round, I cleared all rounds and got offer letter as well. But I had another offer hence I declined.