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What I’m trying to do
Actually I'm using obsidian in windows and trying to create date on template by using templater So, I use this syntax <% tp.date.now(Do-MMMM-YYYY)%> once I press Alt+R (replace templates in the active file) it shows the result for example, 8th-August-2023. that's fine, but when I'm trying to use that option again it's not working, means it's just showing the 8th-August-2023, and the replace templates in the active file option doesn't work for the second time.
Things I have tried
And I checked the plugin, it is up to date.
As you say, you have replaced the template in the active file, so the template has been run and is no longer in the file.
To replace it, paste in the code again, or just create that code as a template and insert that, optionally with its own shortcut: I use CTRL OPT CMD ENTER to insert a Templater date-and-time code (
<% tp.date.now("YYYY-MM-DDTHH:mm") %>) into my notes multiple times a day.