all is in the title.
sometimes, some tickets are closed too quickly, with not enougth feedback of sender.
and sometimes, it doesn't work, and the ticket shouldn't be closed...

so,is there a way to reopen a ticket on github ?

We close tickets ca. after 3 weeks generally if the reporter does not provide enough details or does not respond at all. Especially if we cannot reproduce it.

Generally there is a "reopen" button at the end on each ticket.

I can't see any "reopen" button...

It's right below the comment field, left of the "Comment" button.

again, I can't see any "reopen" button, left of the "Comment" button...

so I comment closed ticket here : https://github.com/zenphoto/zenphoto/issues/238

It is possible that this is visible only to the users allowed to make changes to the repository. That would then be unfortunate. Possibly you should complain to GitHub about not having this feature. At least it would be nice for the developers to know what things are visible only to them so we do not have this confusion.

If you comment is about the GoogleMaps ticket, then the real problem is that you have not got the latest of the 1.4.5 releases. For development releases you do really need to monitor changes as they can impact almost anything you might be doing.