A Call of Duty player who said he was “wrongfully banned” from playing CoD game Modern Warfare 2 took his grievances directly to publisher Activision by visiting its Austin, Texas, office on Monday, as reported the following day by PC Gamer. He was reportedly turned away by security personnel and relayed his story in a now-deleted post on the r/activision subredditsaying he simply wanted to speak to someone face-to-face since he wasn’t having any luck over the phone.

Activision didn’t immediately respond to a request for comment. Various game developers, however, have reportedly criticized the player’s move, saying they worry about disgruntled gamers showing up at their offices in person. But the player’s post also brought to light an issue some Modern Warfare 2 players say they’re facing.

A look at the r/activision subreddit shows players looking for reasons why they’ve been banned from Modern Warfare 2, primarily those who play the game on PC. Some say they were banned for playing the single-player campaignothers say they were banned after playing the game’s beta back in Septemberand others say they’ve been penalized for having hardware-related software on their computer.

There are also threads from individuals who say they’ve tried to appeal their ban only to have the appeal automatically denied. Others who say they were unbanned found themselves banned again not long after.

Read more: Will Call of Duty: Modern Warfare 2 Run on Your Laptop?

Insider Gaming reported on Monday about some of the hardware/software combinations that might be causing the bans by triggering the Richochet anti-cheat system for Call of Duty games. This includes Logitech G Hub, Corsair’s iCue, Razer Synapse 3 and MSI’s Afterburner. These programs allow gamers to change various hardware settings on their PC or the color lighting on their keyboard and mouse, but none are used for cheating in a game.

There’s a Code of Conduct for Call of Duty focusing primarily on banning cheaters and those who bully or harass other players. Developer Infinity Ward did create a public Trello board for Modern Warfare 2 issuesbut false bans aren’t listed.

Infinity Ward didn’t immediately respond to a request for comment.

Modern Warfare 2 is a sequel to 2019’s Modern Warfare, and both games are reboots of the Call of Duty: Modern Warfare games released in the late 2000s. Modern Warfare 2 launched on Oct. 28, but players who preordered the game were able to play before the launch date. Publisher Activision Blizzard said on Monday that Modern Warfare 2 sold more than $800 million worldwide in its first weekend.