Target database.table1 must be delta table

[AkankshaGupta]

I created a table1 with some data. Then I truncated it to load new dataset.

When I do

select * from table

. I get row count 0.

But when I am trying to copy into using following command. I get error saying target table must be delta table:

COPY INTO databse.tabl1   FROM '/mnt/blob/path/tday'  

FILEFORMAT = CSV 

  --PATTERN = 'folder1/file_[a-g].csv'
  FORMAT_OPTIONS('header' = 'true')

I can also see the table in SHOW TABLES.

Please tell me if I am missing anything??