Four ways, and which one you want depends on what has gone wrong.
Best for a question about one customer
Open it next to the line you are asking about. The panel attaches the customer, the servers their line is on and when it expires, so nobody has to work out which of your customers you mean and nobody has to ask you to paste a username.
Best before you have an account
The chat button is on every page here. Use it when you have not signed up yet, or when the question is about buying and not about a line: what a credit costs, whether something is worth trying.
Best when it needs to be quick
For when it will not wait for a ticket. A customer on the phone, a line that should be live and is not, that sort of thing.
Best for anything that needs a record
The slowest of the four, and the right one for billing, an arrangement, or something you want in writing.
Look at the client view first. It tells you whether the customer is connected at all, and whether their box is getting a picture. If it shows both, the trouble is at their end, in the receiver or the dish. If it shows nothing connected, the file usually never made it onto the box.
It appears by itself. Credits land on the account as soon as the payment clears. There is no code to redeem and nothing to send us. If it has been more than a few minutes, that is worth a ticket.
The Netherlands. The servers are elsewhere and deliberately unremarkable, which is the answer to the question everybody asks next.