Apex Legends (Steam) stuck in infinite loading screen

When launching Apex Legends (Steam version), it gets stuck in an infinite loading screen and does not proceed further.
I reset my PC and downloaded Steam as is and started Apex and this problem still occurs...
When I received my EA account data via email from the account management screen, I found a record of "BANNED_ACCOUNT_TAKEOVER", which suggests that my account may have been hijacked in the EA system.
However, I have no idea what may have happened to cause any unauthorized access.

I have tried the following troubleshooting steps, but none of them have resolved the issue.

• Game & Network Related
  • Restarted router & tested with a different network (tethering)
• Steam Related
  • Verified game file integrity (Properties > Verify integrity of game files)
  • Cleared Steam cache (steam://flushconfig)
  • Launched Steam as Administrator
  • Disabled Steam Overlay (Properties > Disable Steam Overlay)
• EA Account Related
  • Checked Steam and EA account linkage (EA Official Site)
  • Installed EA App and attempted login

• Windows Related
  • Performed system file repair (sfc /scannow & DISM /Online /Cleanup-Image /RestoreHealth)
  • Temporarily disabled Windows Defender & antivirus software

I created separate accounts with EA and Steam but the same bug occurred.
Could this be a problem with my PC?

Any help from Apex support would be appreciated.

I'm Japanese, so I apologize if my English sounds unnatural...