c# - Cannot resolve method between Enumerable and Queryable candidates -

i have method in class called invoice:

public static expression<func<invoice, bool>> isallocated() {     return => i.totalamountdue == i.getallocationstotal(); }

i have list this:

iqueryable<invoice> invoices

and need filter (it's linq entity):

var filteredinvoices = invoices.where(i => invoice.isallocated());

in line i'm getting 2 errors:

cannot resolve method ... candidates .... 1 in enumerable , other on in queryable.

and also:

cannot convert expression type expression<func<invoice,bool>> return type 'bool'

i've tried lot of things i've found in no luck. can me missing here or @ least, 1 of 2 errors @ root of problem?

your method returns appropriate expression tree - need call it, not call in lambda expression:

var filteredinvoices = invoices.where(invoice.isallocated());

UV code