Total from Subform to Mainform, #NAME error. (1 Viewer)

Hello.

I'm currently creating a databse for my ICT coursework at A-level.

I've followed multiple guides to achieve what I want. To no avail, I can't get the Total sum from the footer of the subform to be displayed in a text control on the main form.

I've attached my database below.

The Main form is frmInvoice, and the subform is sfrmProduct. You'll see the SUM at the footer of the subform and the text control on the main form is the Materials Cost one with the #NAME? error.

I've been trying to figure this out for days please can someone help.

View attachment Invoice Database .zip

The name of the subform control/container in the form frmInvoice isn't what you've, but child33. Correct it and doesn't show the #NAME error.