I put it on my social media in 2015ish and in 2016 put it in print on tshirts with it being used in a shirt design with more art on it. In 2017 when the next season came my basic version of it was used with their words and a change to the design was used on marketing and their shirt designs. Would you like me to send you the designs by pm to see?
Please don't send me the design. We cannot do personal reviews on this forum.
Did you register your design? If you believe someone has infringed on your artwork, your work must be federally registered prior to filing suit.
If you did not register your work prior to infringement, you will not be eligible to collect statutory damages ($750-$30,000/infringement) and instead can collect only on demonstrable profits made by your infringer or demonstrable losses suffered by you as a result of the infringement.
Not all that appears infringing will be judged infringement in court. There are several factors that are used by a court to determine infringement. The alleged infringer also has several defenses available, including independent creation.
Edit to add: Seeing an IP attorney in your area to do a comparison of the works is a smart action to take. The attorney potentially can send a cease and desist letter to the alleged infringer along with a settlement demand letter.
Good luck.
