Sent off a complaint via the online web form to customer relations regarding 2 issues I had with a recent flight in F. It has now been 10 days since I sent my complaint off and so far all I've received is a message saying they have received my message and have given me a case number.

Should I give it a few days longer, should i just pick up the phone and give them a call.

Is the online web form the best way to sent in a complaint or should I have written a letter and mailed it off to them.