=arrayformula(UNIQUE(
{
IFERROR(FILTER('New Bets'!A3:H,'New Bets'!I3:I<>""),{"","","","","","","",""})
;
IFERROR(FILTER(Alertas!A2:H101,Alertas!I2:I101<>""),{"","","","","","","",""})
}))
=UNIQUE(A3:H)
When I use Unique separately from the rest of the formula, it correctly returns only one row with data, without duplicates. But when using inside the formula, it returns two equal values.
I wonder what I'm doing wrong.
Link to Spreadsheet:
https://docs.google.com/spreadsheets/d/1sv1B1mYrhpzS-ZtCLfLkVPtbffWq231woEX_qOxiAXA/edit?usp=sharing


