How to reassemble front collision plate of robot

Replacing a wheel in a Ikohs/Create S15, is there any service manual how to reattach the front collision plate which got accidentally dislodged, insufficient switch gap when reassembling it, attaching the bottom "chin", it should be similar to some Neatsvor, Valubot, Tesvor robots, thank you for any informations.

I'm bewildered/stumped, also difficult to describe, but here it goes :

this is what it looks like, there are 5 mounting slots/channels on top, both robot and collision plate

once inserted gently into channels from the top, this is how it looks, like this there is sufficient switch play and the robot goes forward :

this is what it looks like from below, you can't see the switches inside the gap, about 1 mm, but it seems sufficient leeway by turning the robot on :

I suspect the problem could be reattaching the bottom "chin", this is how it rests by aligning the screw holes gently :

it seems to me the chin is misaligned wrt to those 4 ridges on the robot's bottom, and screwing them back on it looses any "play" somehow, it's been working for about 5 years so it could have deformed somehow, so that the top part is possibly splayed outwards ? or something really finicky/fussy/particular ?

There wouldn't be any signs of visible damage or deformation that I can tell.

I circled where the switch contacts the collision plate/bumper which is worn due to usage :

the switches would seem undamaged, and it works with just the top half of bumper slotted on, also the top and bottom of robot seem correctly seated together

I can't imagine it being so fussy, it could have warped with usage somehow, otherwise when manufacturing them it would take hours just for the bumper, also bumper reassembly videos on youtube seem fairly straightforward, just screwing the 2 halves of bumper together, not

update : it was a silly mistake, reassembling the robot, the top front fascia with sensors was misrotated about 3 mm, the collision plate of course fits perfectly after reseating it, you couldn't tell from those photos, I circled what it was :