Similar - "Unique Function" on version Excel 2019 and below

Hi everyone, I am struggling to get this but how can I make a formula similar to "unique" function on version excel 2019 and below?

I have this formula in o365 and used the unique function (since it is only available to o365) and couldn't figure out how to do it on desktop version.

Basically, it is a cascading dropdown that is dependent on each other. Thanks in advance 🙂

Dropdown 1

=SORT(UNIQUE(JobCategory))

Dropdown 2

=IFERROR(SORT(UNIQUE(FILTER(JobType,(EntityType=Pricing!B14)*(JobCategory=Pricing!A14)))),"")

 Dropdown 3

=IFERROR(SORT(UNIQUE(FILTER(InvoiceDescription,(JobType=Pricing!C14)*(EntityType=Pricing!B14)*(JobCategory=Pricing!A14)))),"")

Dropdown 4

=IFERROR(FILTER(MinFee,(InvoiceDescription=Pricing!D14)*(JobType=Pricing!C14)*(EntityType=Pricing!B14)*(JobCategory=Pricing!A14)),"")