pp Thanks for reaching out. The error message you are receiving indicates that the revision suffix you provided is invalid because a revision with the same suffix already exists. This can happen when you try to update the ingress for your container app and specify a revision suffix that has already been used for a previous revision.
To avoid this error, you should use a unique revision suffix each time you update the ingress for your container app.
do let me know incase of further queries, I would be happy to assist you.