Why unar extract old rar file?

There are 2 rar files in my scenario, their names are 1.rar and 2.rar. My purpose: 1.rar extract to folder1 and 2.rar extract to folder2. First, I extract the 1.rar file to folder1 folder with unar (unar -o folder1 x/1.rar). Everything is good but if I extract the 2.rar file to folder2 (unar -o folder2 x/2.rar) then unpacking 1.rar's data into folder2. Why does it process previous rar file? OS: Centos 7. Scenario codes: [root@vm-app home]# unar -o folder1 x/1.rar x/1.rar: RAR 5 1/1 - Copy.txt (0 B)... OK. 1/1.txt (0 B)... OK. 1/ (dir)... OK. Successfully extracted to "folder1/1". [root@vm-app home]# unar -o folder2 x/2.rar x/2.rar: RAR 5 1/1 - Copy.txt (0 B)... OK. 1/1.txt (0 B)... OK. 1/ (dir)... OK. Successfully extracted to "folder2/1". [root@vm-app home]# ls folder1 1 [root@vm-app home]# ls folder2 1 [root@vm-app home]# rm -rf folder1 && rm -rf folder2 [root@vm-app home]# unar -o folder2 x/2.rar x/2.rar: RAR 5 1/1 - Copy.txt (0 B)... OK. 1/1.txt (0 B)... OK. 1/ (dir)... OK. Successfully extracted to "folder2/1". [root@vm-app home]# rm -rf folder2 [root@vm-app home]# rm x/1.rar rm: remove regular file ‘x/1.rar’? y [root@vm-app home]# unar -o folder2 x/2.rar x/2.rar: RAR 5 2/2 - Copy.txt (0 B)... OK. 2/2.txt (0 B)... OK. 2/ (dir)... OK. Successfully extracted to "folder2/2". [root@vm-app home]# ls folder2 2 [root@vm-app home]#