Yup I should have tested them separately my bad. I managed to remove the template node and test, still I get the same results , The value on the UI doesn't change unless I manually click the timestamp ( inject node ) to inject some value.
my node-red version is v12.19.0
UPDATE: I started over and created a new time stamp node and it fixed my issue, It seems the update interval was the problem. Thank you very much @Colin