list<Temp_Invoice__c> tempInvoice = [select id,First_Name__c,Last_Name__c,Email__c from Temp_Invoice__c limit 1];
tempInvoice.First_Name__c = billing.billingfirstname;
getting error as Initial term of field expression must be a concrete SObject:List
Best Answer
if you're assigning to a list of invoices, you should be consistent ;)
Note the
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