bootstrap datepicker setDate format dd/mm/yyyy

a bit change in format

format : "DD/MM/YYYY"

Changing to format: 'dd/mm/yyyy' didn't work for me, and changing that to dateFormat: 'dd/mm/yyyy' added year multiple times, The finest one for me was,

dateFormat: 'dd/mm/yy'

Change

dateFormat: 'dd/mm/yyyy'

to

format: 'dd/mm/yyyy'

Looks like you just misread some documentation!

There is confusing when you are using data picker, for bootstrap datepicker you have to use following code:-

$( ".datepicker" ).datepicker({
   format: 'yyyy-mm-dd'
});

and for jquery datepicker following code must be used:-

$( ".datepicker" ).datepicker({
       dateFormat: 'dd-mm-yy'
    });

So you must be aware which date picker you are using, that is ultimately solve your issue, Hope this hepls you.