You probably joined the dawnguard or attacked one of the vampire clan at some point. Sheathe your weapon/magic before entering and they might chill out. This only works once, so if that fails you might need console commands to fix it.
I’m not sure which command to use but I recommend creating a separate save file before messing with this. Sometimes flipping these settings will mess with certain quests and create glitches.
You probably joined the dawnguard or attacked one of the vampire clan at some point. Sheathe your weapon/magic before entering and they might chill out. This only works once, so if that fails you might need console commands to fix it.
https://en.m.uesp.net/wiki/Skyrim:Console
I’m not sure which command to use but I recommend creating a separate save file before messing with this. Sometimes flipping these settings will mess with certain quests and create glitches.