Am unable to invite my new friends to my premier team

So the thing is my team was playing premier this episode and we played all the match until today one of my teammates got banned for (625 hr) idk why neither he do and we tried to add out different friends account to the premier team but all it says is something like "skill issur" I can't recollect it properly we tried many of our friends account all have the same issue what can we do on this