No chest spawns on the top floor of SW Apollyon

Hi,

This is my first time posting in the forums here, so apologies if I have missed something or have posted in the wrong place (I did read the sticky and do a search in the forums before I posted). My issue is regarding the fact that I've had 2 consecutive occasions where no chest spawns on the top floor of SW Apollyon;

Platform: Windows

ISP: EE

Type of Internet Connection: Broadband (Ethernet)

Internet Connection Speed: 8MBPS

Date & Time: 26th of December 2018, 01:26am GMT

Date and time of when the issue occurred. 25th of December 2018, approximately 7pm, and again 26/12/2018 at 01:05am

Frequency:On every occasion of entering SW Apollyon since 25/12/2018

Character Name: Kairyu

Race: Hume Male

World: Asura

Main Job: Puppetmaster 99

Support Job: Thief 49

Area and Coordinates: SW Apollyon Floor 4

Party or Solo: Solo with Automaton

Monster Name: Elementals

Steps:

1/ I entered Limbus (SW Apollyon) approximately 7pm GMT on 25/12/2018 on (I believe) Darksday, and ascended the first three floors of SW Apollyon (On the first two floors i used Valoredge head/Sharpshot body, and the third floor I used the Spiritreaver head/Stormwalker frame).

2/ On the fourth floor, I proceeded to defeat the various elementals with the Spiritreaver Automaton using Overdrive and Heady Artifice (each spell would one shot the elementals), and continued in the same fashion once the 1 hour abilites wore off.

3/ Once all the elementals were defeated, I looked through the floor for the chest as I didn't see it spawn. I used Flee and ran around a few times but did not see a chest. I also looked through my log for a notification regarding a chest or the floor being cleared, but saw nothing.

4/ I contacted a GM (Unfortunately I cannot recall their name), whom responded about 10 minutes later. Before they responded I tried logging out and back in to see if it would help, but it ejected me from the battlefield with no credit for clearing the floor.

5/ I explained everything to the GM, who breifly looked into it and advised that it could be an in-game bug as poopsed to a technical issue, and advised I post in the forum.

6/ I logged out some time after and logged back inapproximately 12:30am GMT on 26/12/2018 and decided to try and do another run. I went back to SW Apollyon (Entered on Firesday) and cleared the first three floors with the Valoredge head/Sharpshot body setup with no issues, meleeing alongside my Automaton.

7/ On floor four i used the Spiritreaver puppet and my 1 hour abilities again, but this time i also killed some elementals by meleeing/weaponskilling with my main character. I periodically ran around the zone while killing the elementals to see if a chest spawned somewhere.

8/ Upon defeating all of the elementals, once again there was no chest to be found or any messages in my log. This time I stayed in floor four until i timed out of the zone, and ended up being ejected from the zone with no credit for clearing the fourth floor.

Update
9/ I went in again as RDM99/BLM49 onthe 28th of December 2018 around 16:50pm GMT on Darksday, and had the chest spawn upon clearing the final floor. I used a combination of nuking and meleeing (Nothing I have on this job could one shot the elementals on this floor). By the time i got to this floor it was firesday and the last elemental I defeated before i noticed the chest was a light elemental (There were still water and earth elementals on the floor).

Just pure speculation, but maybe the issue could be automaton actions not "claiming" the mob? In the same way that if you deploy the sharpshot automaton on an enemy and it uses a ranged attack, the targets name still stays white until the second action. Although I feel like I had previously done runs on Puppetmaster using the BLM automaton and had the chest spawn on the final floor previously. I could be wrong however.