lg g2 stuck on cyanogenmod logo

hello, Yesterday I was trying to upgrade my G2 d802 to cyanogenmod 12. I wasn't able to do a backup cause I didn't have a space, so I skipped on this stage. I succeed to upgrade to cm12 but my calls didn't work (after I set it) so I did upgrade straight to cm12.1 in the upgrade center in the setting. after that my phone was stuck on cm12.1 logo so I put the phone into TWRP mode and I install cm12 again.
Now my phone is stuck on cm12 logo and I can't go to TWRP or DOWNLOAD MODE but my computer detecting my g2.
What I can do plz help me