Query prepending with comma which fails to query

[ajaylankipalle]

Query accountQuery = new Query(Schema.Account.SObjectType) // Query the account object
.addField(Schema.Account.Id)
.addFields(SOQL.FieldCategory.CUSTOM); // Include all custom fields - only fields that are accessible to the user are included

List accounts = accountQuery.getResults();

DEBUG| this.getQuery(): SELECT , Account_Contact_Soft_Credits_Last_Year__c FROM Account;

I am digging into getQuery()