I just booted up Destiny 2 after take a year off (thinking about getting back in for Shadowkeep). I have three characters over 300, but one of the three characters (Titan) has been reset in the main story line. The Titan can only access the Farm in the middle of the main story line. The other 2 characters are fine. Don't know what happened, but how do I get this fixed?
You need to finish the main campaign/story before the tower opens up. Your titan is only about 1/2 way through story/campaign.