I am a video editor...I usually start the job once my client sends the script. It is been a week but still he is not submitting what I need/ the script to get started. He already send an the offer, what should I do? end the contract? I always message him like how are you? When you can send the script to get started.
re: "client become unresponsive"
Clients are under no obligation to be responsive.
As freelancers, we get paid whether or not clients are responsive.
re: "I usually start the job once my client sends the script. It is been a week but still he is not submitting what I need/ the script to get started. He already send an the offer, what should I do? end the contract?"
Your post is not completely clear.
You said that the client sent you an offer, and you ask what you should do.
The answer to this question is always the same:
If a client has sent you an offer, but you do not have enough information or input files to do the work, then you should NOT accept the offer.
Because you do not want to start a contract and then not be able to do any work, resulting in having a zero-pay contract, which will reflect negatively on your Job Success Score (JSS).
So it is always a tactical mistake to accept an offer when it is not possible for you to do any work.
In other words: Receive the script, and then accept the offer.
But then you asked if you should end the contract.
If you have simply been sent an offer and have not yet accepted the offer, then there is no contract. There is nothing to end.
But if you HAVE already accepted the offer, and a contract is in place, then there is really nothing you can do but wait.
If the client wants you to create something for him using a script, and he has not sent the script, then you can't do anything. You already messaged him. That is all you can do. Do not continue to send him messages. That will not help.
If this is a fixed-price contract, then there is nothing you can do but wait. Eventually he will contact you or Upwork will close the contract automatically if it sits inactive for a long time.
IF THIS IS AN HOURLY CONTRACT (which does not seem to be the case, but I'm just giving a complete answer here)... Then you CAN go ahead and start working on the project. Maybe you can only work for ten minutes. But that's enough so that you won't have a zero-pay contract. Do whatever you would normally do to START a project like this regardless of the script - set up the file directories, set up the initial project files, make notes about your approach to the project based on your discussions thus far. At least then you will be as ready as possible to get to work on the project once you receive the script.