request for an invoice with no sucess

from Friday 12/12/2025 at 17:57 I have requested for a copy of my invoice till today the 15/12/2025 @12:13 I have not received it. Their reference is *** and I am not happy shame their service is off .That means they can not account for them billing me as i need proof for work purposes that I have wifi at home to be able to be afforded a chance to work from home.