Hello @Diego Klubok
To change the date format of date pickers you need to alter the format in the System settings, under the Look and Feel section.
Though if you are viewing the Issue via Jira's new UI the date format you have specified may not apply. In which case, I would create an Atlassian support ticket via their support page.
Hope this helps,
Jira is a powerful tool that helps teams to plan, manage, and report on their work. We love using Jira, especially for its ability to track issue progress. But how to monitor the...
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