Mark Andrews, Curtis Samuel or Tevin Coleman as FLEX?

Who should I pick as my flex? Mark Andrews, Curtis Samuel or Tevin Coleman. Im 1-3 in my 12 team standard league.

Bonus question… any player that I should trade? What can I get for Mark Andrews?

*bye weeks are next to players.

(11)QB- R. Willson
(7)RB- N. Chubb
(12)RB- D. Johnson
(10)WR- J. Edelman
(9)WR- R. Woods
(4)TE- G. Kittle -
(8)FLEX- Mark Andrew
(10)K. J. Elliot
(8)DEF- Ravens

BENCH
(8)WR-M. Gullup gone for 2-4 weeks
(6)DEF- Bills for week 7-11 stretch
(4)RB- Tevin Coleman didnt practice monday
(6)RB- T. Singletary - gone for 2-4 weeks
(10)RB- C. Thompson
(7) WR- Curtis Samuel