Every time I get a vanguard mentor missive I only get the same 3 bountys for the thorn,bad juju,and invective. I have tried completing one to see if I could get new ones but it didn't work I've also have tried to hold onto one of them but the next time I get a vanguard mentor missive he only had the other 2 I didn't pick up. How do I fix this? because the only exotic I need is the super good advice and it is annoying because this bug has happen about 8 times