addUserToGroup stopped working

[ghost]

ERR! addUserToGroup {
ERR! addUserToGroup   __ar: 1,
ERR! addUserToGroup   error: 1545052,
ERR! addUserToGroup   errorSummary: 'User cannot be added',
ERR! addUserToGroup   errorDescription: 'The user cannot be added to the conversation. Please try again later.',
ERR! addUserToGroup   payload: null,
ERR! addUserToGroup   hsrp: { hblp: { sr_revision: 1003441264, consistency: [Object] } },
ERR! addUserToGroup   lid: '6938751308900240789'
ERR! addUserToGroup }

[TheSohaibAhmed]

Are you sure that you're the admin to the group and can add people to it? Did you also try checking threadInfo to see if there are any limitations?