I am having trouble trying to do this mission. It keeps telling me I must complete a prior mission. I have done the Styrll Infiltration mission and the Styrll Target mission 4 times, but can't get this mission to re-open for me. Am I missing something? Or is there a glitch preventing me from accessing?

You only do Stryll Infiltration twice, and you do A Stryll Target 8 times. Did you do The Genetarr Capture?

The game needs to tell people exactly which mission they need to do; people ask about this at least twice a month I think.

Is it not just a chain?

I have the same issue man .... it's a glitch somewhere cause at some lower rank it became available to me... I did it 30 times out of 80 , then i did some other missions .... all the sudden I need to complete a prior mission.... still haven't figured out which one I have to do ??????? DAN ????

The order

Stryll Infiltration
A Stryll Target
The Genetarr Capture
Thoughts Revealed
Tracking the Contacts
An Urgent Escape
Signature Disruption
Seal of the Genetarr

This "glitch" usually occurs when you've completed one of the non-holiday timed missions... these missions are usually individual chapters in a sequential series, and after the last mission in the series disappears from the timed missions section, the entire series (once again, if it was not a holiday timed mission) comes back as a non-timed mission... when it does, it will usually just show the first mission in the series, with one little exception... if you have fully completed all repetitions of a single mission when it was marked as a timed mission, you will see the next mission in the chain as well when the series comes back as non-timed, but the button on that one will be grayed out and it will just say you have to complete a prior mission. (ok, don't try to make heads or tails of this paragraph.. your brain might explode)

Personally, I think the mission shouldn't even be shown if it's waiting for you to complete _any_ prior missions in the series