Lua Defense enemy under map

[(PSN)AngelOfDeath765]

Hi I have a little issue with Lua Defense missions. Most of the time I play them the last enemy that has to spawn before the floor collapses spawns underneath the map, unable to be damaged. Is there a way to fix this in game so if it happens again I can still progress through the mission without having to restart? Thank you. (The link below is a photo I took of the issue. I can't seem to add the photo directly to my post) 

 

https://imgur.com/a/qcthKd1

[(PSN)teacup775]

legion know your pain.

[(PSN)Vexx_IV]

I also got on here to report this.  DE I love you and all that you do, but please, please, PLEASE, fix this bug or remove the Lua defense map from sorties altogether.  I am not exaggerating when I say this happens to me every single time that this defense mission pops up, although it's not always necessarily on the 5th round just before the floor collapses.  Last night's 3rd sortie mission was this Lua defense, and after having the same thing happen 3 times in a row I finally gave up trying.  In total with those 3 rounds that I had to quit plus the completion of the first 2 missions plus preparing my builds beforehand, I easily wasted 45 minutes to an hour for absolutely nothing.  That's a little frustrating when considering I typically only have an hour or two to log at night.