This tape measurer is stuck. The metal piece is stuck (where orange arrow is pointing).
How do I unstuck it?
Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. It only takes a minute to sign up.Sign up to join this community
The metal clip which extends out of the case is attached to the top of the metal tape. It often has some play to account for inside versus outside measurements, which can lead to the metal tape getting a slight bend.
The bend can become severe over time and curl backwards and downwards, blocking the slot from which it exits.
One would hope that the clip can be pulled away far enough to view the case slot from the clip slot. The next task is to insert a thin blade through the clip slot and into the case slot, ostensibly to push the folded portion of the tape flat enough to pull it outward.
As suggested in the comments, this type of tape is frequently cheaply made. Once the tape takes a bend, it's impossible to prevent it from snagging in the future.
Opening the case is risky as the internal spring wants to go sproingy and exit in an uncontrolled manner.
The problem is sort-of about the tape measure. But really about measuring "We are looking to get large monitor and need tape measurer".
If I don't have a functioning ruler or tape measure handy, I grab some paper to figure it out. This doesn't work for measuring a room, but for a monitor - either to figure out the size of an existing monitor or to measure (roughly) the space available for a monitor, just grab some ordinary paper.
The details depends on where you are - in the US, the standard is letter size = 8.5" x 11". That gives you two sizes right away - 8.5" and 11". Subtract (fold diagonal to get a square and then you have a rectangle leftover) gets you 11" - 8.5" = 2.5".
With various combinations (e.g., 11" + 8.5" = 19.5", 11" + 11" = 22", 11" + 2.5" = 13.5") you can get a reasonable measurement within an inch or so for anywhere from 2" to 30" without much trouble. Not perfect. But measuring for a monitor doesn't generally require high-precision.
If you are trying to measure for a big monitor - e.g., 50" and up "wall size", then it is a different story - paper becomes far less convenient as a workaround.