Send error messages when people don't use commands properly

[technonerdz]

Some people are trying to subscribe to teams using their name instead of their number. Right now, the bot tell them that they have successfully subscribed to the team but it doesn't actually register their choice in the database.

Some people also tries to subscribe to multiple teams using commas like: Subscribe 123,456,1234,1243 wich doesn't work. The bot only look at the number and they will get subscribed to team 12345612341243 wich doesn't exist.

We can't really do a script to get team number by name because some teams that have the same name and it would be a nightmare.

What we can do is send an error message when it can't find a valid team number in the request.