I got this error mesagge when i try to save an apointment on the calendar app. Hope anyone could help with a solution. Thanks!!

Fallo al renderizar la plantilla <Template memory:53b7a10> usando los valores {'format_date': <function MailTemplate._render_template.<locals>.<lambda> at 0x09879A98>, 'format_datetime': <function MailTemplate._render_template.<locals>.<lambda> at 0x09879B70>, 'format_amount': <function MailTemplate._render_template.<locals>.<lambda> at 0x09879E88>, 'format_duration': <function MailTemplate._render_template.<locals>.<lambda> at 0x09879348>, 'user': res.users(2,), 'ctx': {'lang': 'es_MX', 'tz': 'Mexico/General', 'uid': 2, 'allowed_company_ids': [1], 'color': {'needsAction': 'grey', 'accepted': 'green', 'tentative': '#FFFF00', 'declined': 'red'}, 'action_id': 127, 'dbname': 'accesocorrecto', 'base_url': 'http://192.168.88.190:8069', 'force_event_id': None, 'safe': False}, 'object': calendar.attendee(9,)}  

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