[otrs] Allowing agents to always select a customer code

Hi, I'm in the process of customizing an OTRS 5 installation. When creating a new ticket, the customer code is grayed out, unless you select an already created customer. I would like to allow the Agent to be able to select the customer code, even if the customer doesn't exist. We don't know in advance who is going to contact us from an organization so the customer is usually the email, and the customer code is the company name. We do have a list of customer code. - How do I allow the agents to always be able to select the customer code? - Same question about services. I want the agents to be able to select all the services. I think this can do this with ACL's? Anyone who has done this? Regards, Benedict