The Chamilo community provides different levels of support depending on your contributions, involvement and resources.
Get free help from the Chamilo Community at https://forum.chamilo.org.
If you don't have an account, you will need to create one and wait to be approved, which usually takes between 1 and 72h (3 days) as it is a manual process managed by volunteers to avoid massive SPAM accounts creation. Hold with us for a bit there, it's probably worth it.
The Chamilo forum provides all types of support levels.
Developers usually hang out on the Chamilo Slack channel these days. If you have more of a technical issue and speak the developers language, connect at https://chamilo.slack.com for direct interaction with us, but be ready to provide a lot of details and wait for a bit, as we might be busy with other important stuff.
The Github issues queue is not a place to ask questions. It is meant to report clear and concise bugs or feature requests. Support questions are not answered in a timely manner, most of the time.
Not to say that the other channels are not professional, but...
If you have urgent needs that impact your efficiency or sales as a business, you have the incredible opportunity of getting things done by official providers of the Chamilo Association. These incredible companies are expert in all fields related to Chamilo, know each other so they can recommend you to other providers if they feel these will better serve you, and contribute back to the Chamilo project each year (and continually for some).
Get in touch with them preferrably before getting into an urgent problem. Just have a support contract proposal ready so that, when you hit an issue, the process of fixing the issue is not slowed down by administrative issues.
You can write to all Chamilo providers at once by writing to providers at chamilo.org.