If your account has been frozen due to suspected fraud you are looking at 7-28 days to sort it out not 1 or two days.
The people you are ringing know nothing and could not tell you anything even if they did, because that is also how fraudsters used to work by 'blagging'.
The fraud team are not contactable by customers and they have a backlog of work. That's why the delay. They are not doing it deliberately to fox you. They will have performance metrics so the quicker things are cleared the better for them, but they can't do that until someone has actually looked at it which will take a while.