ERJ 170/175 Flight Attendant reported an injury caused by the main cabin door liner not positioned correctly; causing her hand to be pinched between the door operating handle and the liner. This resulted in an aircraft change.

Narrative

When I arrived at the airport in ZZZ; I noticed that the door flap for the 1L door was protruding out quite a bit. I disarmed the one L door at the gate; and quickly did a test of my flat hand in to grab the white main handle and slightly pulled back and noticed that my hand had pinched between the main handle and the cover flap. This has been an ongoing problem and I have been told to continue reporting this. I informed the Captain and he and every crew member on board tested and had the same issue of their hands being pinched as well. Maintenance was called and arrived which resulted in a lengthy delay and which eventually I saw the entire door covering removed. We were advised that another aircraft had arrived and we would be switching gates; so when we arrived to the second aircraft the same issue applied with that lining cover for the 1L door as well. We informed maintenance and the Maintenance Staff as well had the same issue of their hands being pinched. In this case; because there was no prior damage to the molding of the door; they were able to adjust the bracket so that the lining cover sprung into place with enough allowable room for everyone to operate the main handle door properly. Every door in our entire fleet should be tested; and certified before sending into service. It is not a preflight for the Flight Attendants at this time to check that main handle door. However; it is obvious that it is a failure. I don't know why this isn't done across our fleet as serious bodily injury would result for anyone operating that door in emergency mode.