Localhost:

Production (nginx + gunicorn):

Do you have any idea why this happens? And it happens only in polish. German, japanese, english and spanish work perfectly on production as well.

Settings.py:

LANGUAGE_CODE = "en-us"

LANGUAGES = [
    ("pl", "Polski"),
    ("en", "English"),
    ("es", "Español"),
    ("de", "Deutsch"),
    ("ja", "Japanese"),
]

LOCALE_PATHS = (
    os.path.join(BASE_DIR, "locale"),
)


TIME_ZONE = "Europe/Warsaw"

USE_I18N = True

USE_L10N = True

USE_TZ = True

HTML:

{% for concert in concerts %}
    <div class="detailed-page-text calendar">
        <p class="concert-title">{{ concert.title }}</p>
        <p class="concert-date">{{ concert.date }}</p>
        <p class="concert-time"><bold>{{ concert.time }}</bold></p>
        <p class="concert-location">{{ concert.location_main_name }}</p>
        <p class="concert-address">{{ concert.location_address }}, {{ concert.city }}</p>
        {% if concert.link_to_details %}
            <a class="more" href="{{ concert.link_to_details }}"> {% trans "More" %}</a>
        {% endif %}
        <br>
    </div>
{% endfor %}

I tried clearing nginx cache manually – no result.
restarting, reloading server. Did not help much.

I have also restarted gunicorn and gunicorn.socket. No result.