My company has one service desk that is used for all kinds of requests from custom reports to ordering computers to fixing bugs. The requests all come from email into one issue type, IT HELP. We then want to change the issue type based on the request (this is mostly have to be done manually).

It doesn't seem like I can change the issue type once created, is that correct?
I tried automation and it gave me the option to change the customer request type but then it didn't update to the workflow for that type.
Does anyone have a service desk set up this way and can provide some guidance? Thanks.