1) i bought several times boostservice over years, all done it in solo que (maybe i just lucky if you say alot do in Teamque, idk about this "fact") and i had never problems. If you dont do it normal way you should inform me about that (Especially if you combine other Boosting Accs into Teamgames), because otherwise im going out by the fact you doing the Service normal)
2) thats not right, my acc got banned at 4170, not at 4300 ( i can proof that if needed)
3) if its means nothing, why u say "
BEFORE 4000 MMR I'll play only supports 0% CHANCE to ban " ? And why I think u play support only until 4K, and when i login into my acc i see a lot of games were not Support until 4k ? And even if you would had done this, its getting erased by the fact you playing in Team with another Acc which is doing exactly opposite.
Now after some days past i analyzed the History of my Acc and i can tell you why it got banned:
You played aloth with different Teams ( Games were partly mixed from crusader to Immortal )
Doing it like this is not "
BEFORE 4000 MMR I'll play only supports 0% CHANCE to ban", you can call it "
High Risk Boost, combined Acc-boosting with other Boostaccs in Same Team,all Roles, atleast 50% Banchance"
I explain you why:
1: If other Accs getting banned, which were in Team together with mine, your raising the chance for my Acc getting banned just by the Fact you are teaming with potential risk ( because its not normal Accs).
2: Games were mixed in a very big Scale, System just detect Acc´s are playing in Party and for Example ( Crusader,Archon,Legend Accs which getting boosted too) overperforming alot in this huge difference MMR mixed Games. System will send after unknown series of games like this warning about MMR Abuse suspicion.
3: System or Valvestaff look now at History and see: Crusader in Party with me and overperforming in alot of Games.
4: I See you did also changed alot Teammembers in Teamque-Games: The Result ist: System see everytime outscaling Performance of different Accs which playing with me together, it raises intern warning about MMR Abuse suspicion.
5. By playing in huge MMR-Difference Teamque games the Chances raises to get manual Player Reports by outperfoming Players which are for Example +1-2K MMR more than me.
If i read "
BEFORE 4000 MMR I'll play only supports 0% CHANCE to ban" i think this Booster Guy is knowning about how to boost. But if i login and see he didnt done that and done alot of other things which raise the chance to get banned im just freaking out,
4) This is an Argument if you would had informed me about the high Risk Method you are using ( Putting Huge Difference MMR Boost Accs together in Same Teams in alot of Games and playing all Roles)
Here are Proofs for what you had done to get my Acc banned:

You are playing Legend 4/5 ( now its just Ancient 3) and stomping Divine 5 in Mid.

You are playing again at 3,8k~ mid and stomping the **** out of Divine 3, while your Safelane mate (which is getting boosted too) stomping as Ancient 5 another IMMORTAL player !!!
Now comes a very funny game for Bandetection !!!! A ****ing Archon 2 Carry beats the **** out of Immortal Carry in other team.
You cant Team with Archon 2 Carry boost Acc, which is stomping a team with Immortal Carry Player. Ofc System detect this !!!!
5) For this **** youve done with my main, i should get all my money back + refund acc for free.