Yes the contrast bias is off, has shifted. Usually there is a miniature pot to adjust it,
or a R divider to set it. If one R on the divider is badly soldered or poor connection
that can also create this problem.
Note the contrast pin on your display is labeled VO, third pin from left in your pic.
The manufacture may have put the pot / R divider underneath the display. Usually
pot is 5K to 10K, so worst comes to worst you could "over power" it by attaching a 1K
pot to VO to get bias right. Thats assuming pot has not shorted in failure. You might
measure VO to ground to see whats its R looks like.
Regards, Dana.