Adonis .paginate(): total and lastPage data is wrong

So im using PostgreSQL as my DB,

Here is my Query:

await Order
      .query()
      .select('delivery_date')
      .groupBy('delivery_date')
      .paginate(page, count)

I have a total of 15 items in this query, but when I used the .paginate()
where page = 1 and count = 5

the result that game me is:

data: [....]
lastPage: 1
page: 1
perPage: 5
total: "5"

and thats not right, lastPage should be 3 and total should be 15 (if total is referring to the current items I think its okay), but there should be a way to get the overall total items without querying again