This is what my relic 5 - 7 is experiencing.

Some teams counter others. Some don't. 

Palp wins not by being tanky or doing the most damage. He wins by churning through bonus TM and using AoE stun to prevent you from doing anything on the few turns you get. 

If they're faster than you and get their TM train rolling first, they will cycle infinite turns and will eventually crush you. 

So How do you stop that? Well! 

Hux prevents TM gain while he has Advantage if all his allies are First Order. 

Jedi Master Kenobi is even better: If he's lead, then he shuts down all TM manipulation, period. 

Admiral Raddus applies Daze to any Empire toon that gains TM. Which means that they get that first tiny bit of TM then get shut down. 

Spirited Speed is a data disk that allows you to gain TM yourself: 2.5% for every buff you gain. Combined with the generous buffs to Raddus' allies and Cassian Andor's allies to start the battle, you should gain a huge TM boost and can often act first even when the Conquest enemy has a large advantage over you in speed. 

And, of course, there are the Tuskens -- the all time greatest for shutting down TM hopping teams. 

Heck, if you have the right zetas, you can use Jawas and Barriss Offee together and let them stun you, take a million turns, and destroy themselves with thermal detonators. 

can someone explain to me the logic behind that **bleep**?

The logic behind the "bleep" of having some teams counter what other teams do well while other teams counter those in turn is ... that's how these games work. Different teams beat different enemies. Rock doesn't beat paper. Rock beats scissors. Rock against rock will go to a tiebreak, in this case who can pump out debuffs first, which largely comes down to speed, which is greatly affected by the ability "Overprepared" as well as by the sector you're in and how far you are through that sector. 

Don't let your victory rest on a tiebreak that you can't predict (like whether a team whose speed you don't know is faster or slower than your team). 

Bring a hard counter to TM jumping -- First Order with Hux, JMK, Tuskens, Raddus. Those are the sorts of things you need. Not a mirror. And especially not a mirror where you haven't modded your toons for flat out speed bc you normally don't need it with the TM gain. Hardly anyone wastes their best speed mods on a team that gains so much bonus TM, and I doubt you're different.

Conquest is a test of how well you know the mechanics of the game and how broadly you've invested in your roster. One good team isn't enough. You need different ones for different challenges. And you have to know when to use which squad. That's it. That's what Conquest is about.

If you want help in figuring what your options are, just drop a link to your SWGOH.gg account and I'm sure some folks would be happy to offer some helpful advice.