how to resize LVM on leap 15 with hard RAID1

Hi
I did’nt found the answer
I have installed leap 15.0 on my 1To RAID1 DD
I have use all the space to create the LVM … i did’nt know that’s will make problem
I want to create a new LVM machine and i can’t because :

if I try to resize the LVM with yast of corse i cant because volume ares mount
I said it willbe possible with live CD … no the live CD did’nt see raid1 hard disk

I try with Gparted but i got an error message ??

so how i can do that
… backup , erase and re install !!! i prefer not

best regards

may be one solution if none
beak RAID 1

change LVM with Live CD or Gparted
re plug RAID

?? what about