curl to mirror a local Directory to a remote site

Question

I am using a curl like this to copy an entire directory from local server to a remote server:

find . -type f -exec curl -v -k --user 'mikey:pwd' --ftp-create-dirs -T {} https://internalrepo.com/repository/rhel-8-for-x86_64-baseos-rpms/{} \;

and all work fine on my internalrepo I can see all the files. In the next times I would like to upload only the new files (newest then 180 minutes in my example), I am tried to use this unsuccesfully, because the old files are all removed before to copy the new:

nohup find . -type f -mmin -180 -exec curl -v -k --user 'mikey:pwd' -T {} https://internalrepo.com/repository/rhel-8-for-x86_64-baseos-rpms/{} \; &

please if you have some ideas to try I will apreciate it, tks regards Ste