convert downloaded pdf file to human readable string

Im downloading a pdf file from dropbox that I've previously saved to dropbox, created progamatically using HTML Markup. (which is working fine).  But I then want to convert the pdf file to a human readable String so that I can gather specific info from that string.  heres what i've been trying but its not giving me a human readable string.

/** Download pdf file from dropbox **/
        
        // Verify user is logged into Dropbox
        if let dropboxClient = DropboxClientsManager.authorizedClient {
            
            // Download File from Dropbox
            let filename = ((cell?.textLabel?.text)! + ".pdf").lowercased()
            print(filename)
            
            dropboxClient.files.download(path: "/\(filename)").response { response, error in
                
                if let response = response {
                    let responseMetadata = response.0
                    print("dropbox responseMetadata: \(responseMetadata)")
                    let fileContents = response.1 as NSData
                    print("dropbox fileContents: \(fileContents.description)")
                    
                    let encodedFile = String(data: fileContents as Data, encoding: String.Encoding.ascii)
                    
                    print("ACTUAL FILE: \(encodedFile?)")
                    
                } else if let error = error {
                    print("dropbox error: \(error)")
                }
            }
        }

I believe Im having trouble using the proper String.encoding, but i've tried most of them and nothing seems to work.  Any help is much appreciated. Thanks