Am having a SPO site,with SPList with 5300 items and one of the fields must be a unique field. But, because since its crossed 5000 items, i am unable to make the field as unique field. This field is a
single line of text
when i tried to make the field as
Enforce Unique values am getting the below error:
the attempted operation is prohibited because it exceeds the list view threshold enforced by the administrator.
How to perform this uniqueness for this field