I have had excellent service from Marine Traffic. I use the free version
If you click on the Support button on the bottom right hand corner of its page and describe your problem you will probably get a message saying:
"Thank you for contacting MarineTraffic.
We received your request (#46727). We'll review it and get back to you as soon as possible!
We read every message, but as we receive quite a lot of requests, please note that in some cases it might take us a bit longer to respond.
In the meantime, feel free to explore our Help Centre for a list of frequently asked questions and community-powered help: http://help.marinetraffic.com
Have a productive rest of your day!
Your MarineTraffic Support"