A load ID is not the same as an invoice ID/Initial Load ID. The Load ID will not change and is more closely related to the order information. The Invoice/Initial Load ID is for your records and payment. You can create an initial Load to auto-populate in sequence for new orders.
Click on "Settings".

Click on "General Settings".

Add a starting number under "Initial Load ID".

Click on "Save".

Please contact support at 816-974-7002 for more help!