As you may know, we changed parent companies about a year ago, and are now owned by a Swedish company called Modern Times Group (MTG). We are no longer owned by GameStop, and along with this transition, we have removed PowerUp Rewards connections from our site.
On August 29th, 2017, PowerUp Rewards accounts were no longer linked to Kongregate accounts. All previously linked accounts became unlinked August 29th, 2018. This means that Kong+ subscriptions tied to your Power Up Rewards have expired.
In addition, as of July 20th 2018, we no longer accept GameStop gift cards for purchases on Kongregate.com.
If you have any questions, feel free to ask here in this thread or contact support.