To select the competitor, you must first set the status to 'Lost':
Next, under 'Reason sale lost', you can select the reason 'Competitor'.
Additionally, you can specify to which competitor the sale was lost under 'Lost to competitor'. This way, you not only gain insight into which competitors you lost revenue to, but also the exact reasons why.
This provides valuable insights into the revenue lost to competitors: how much revenue is lost to which competitor, and which competitor you are losing the most revenue to.
Competitor list is still empty
If you cannot select any competitors from the list, it means no competitors have yet been added as a relation in your CRM. First, create them in your CRM and assign the 'Relation type' as 'Competitor' on the 'Company information' tab: