Please compare this MicroView with the other. Are the pins much shorter?
If yes, the PCB is not latch properly to the enclosure. With the lens removed, and the OLED flip away from the PCB, press the PCB towards the enclosure really hard until you hear a tag sound or same pin length as the good one. Then flip the OLED back towards the PCB, then put the lens back to the enclosure. The lens should be same height as the enclosure ,flush, completely level or even.
If the unit came with the lens fell out, out of the box, please email firstname.lastname@example.org for a replacement.
Hope this helps.