When going through Scrum training and reviewing sources, I've understood that teams need to stick to the Fibonacci sequence when estimating stories in Backlog Refinement. The purpose behind this being that it's a rough estimate and we do not like to give exact estimates as there are often unknowns or complexities encountered in estimation.
If a team is half and half on an estimate (example: 3 people vote for a "3" and 3 people vote for a "5"), should they need to pick a Fibonacci number and not average it to a "4" as it is not in the Fibonacci sequence?