Don't give security info to non-security people. Use whatever contact method is available to ask for the right security person. Don't give details about what you found until you get someone who will understand it.

Then provide the details about what you found. Don't ask for reward or demand any kind of action or else you are very likely not to be taken seriously. Just provide help and leave it up to them to deal with.

I'm not sure what kind of template you need. Give them the info/steps they need in order to locate the information you found.

Don't give security info to non-security people. Use whatever contact method is available to ask for the right security person. Don't give details about what you found until you get someone who will understand it.

Then provide the details about what you found. Don't ask for reward or demand any kind of action or else you are very likely not to be taken seriously. Just provide help and leave it up to them to deal with.

I'm not sure what kind of template you need. Give them the info/steps they need in order to locate the information you found. If you sound too "scripted" you might sound like a scammer. Be human. Be helpful.