The Receptionist app will report a "Wrong badge size set" error when the application has received an error from the printer after attempting a print job. This is typically caused by one of following situations:
The labels loaded into the printer are not a supported label type:
The wrong sample roll (included with the hardware) was used. Change the roll and double-check that the Brother DK-2251 type is selected on the Printing section of your online account.
A non-Brother roll was purchased. Although other companies claim to be compatible, the app only supports Brother brand labels at this time.
A different label refill cartridge has been loaded into the printer that does not match the selection previously used, and a new compatible roll number needs to be chosen within the Printing section of your online account.
The plastic holder from the previous roll has been repurposed on a new label type. The paper and housing both have identifying markings that the printer uses to verify roll type and these must match. Please ensure the roll is used with the plastic holder it came on.
You can verify the roll type by the sticker on the side of the black plastic holder, or by flipping the housing over. The "foot" has holes the printer uses to identify the roll type, next to a three digit number that match the label type. The roll shown here shows 251, which corresponds to the Brother DK-2251 labels: