How to rewrite the code of a deployment?

In the domain name list, the deployed domain name and the main domain name are placed together, I mistakenly thought they had the same function. I printed and distributed the QR code of the deployed domain name. Later, I found out that this was only for one deployment, and even though I updated the program, the domain name still remained the same.
Is there any remedy now? Because the QR codes have already been printed and distributed, at the very least, I hope that the original domain name, for that deployment, can be redirected to the main domain name if I can modify the code...
Thank you very much!