Please upgrade in CLI:

1.upgrade FD1108s_V2.4.06_200728_X000 file and then reboot

2.upgrade FD11008s_V2.4.06_200728_X000 file again but don't reboot olt

3.upgrade  FD1108s_FW_V2.4.06_200805_1731_X000 file   

4.upgrade FD1108S_WEB_V1.2.0_201028_0936_X000 file then reboot