Getting missing PV error while extending Logical Volume.

Issue

• When attempting to extend a logical volume using the lvextend command with "--devices" option, the following error is encountered:

# lvextend -l +100%FREE /dev/root_vg/opt --devices /dev/sdx
  WARNING: Couldn't find device with uuid T1UjJR-DL0Q-RU3G-XWIc-eDuc-8ouf-IqpkXv.
  WARNING: Couldn't find device with uuid qOKNbg-2voM-0WCa-Gx2s-bq3M-Hg0e-eDivk9.
  WARNING: VG root_vg is missing PV T1UjJR-DL0Q-RU3G-XWIc-eDuc-8ouf-IqpkXv (last written to /dev/sda2).
  WARNING: VG root_vg is missing PV qOKNbg-2voM-0WCa-Gx2s-bq3M-Hg0e-eDivk9 (last written to /dev/sdb).
  Cannot change VG root_vg while PVs are missing.
  See vgreduce --removemissing and vgextend --restoremissing.
  Cannot process volume group root_vg