@Kosken are you sure ? or did you got a TL-SG105E  v4.0 in a TL-SG2210P box? can you post a picture of the device you have and one of the bottom sticker?
Those two are very different devices, 

  @crrodriguez the switch is on the attic so it's a bit hard to reach it, but i will climb up there later today. However, the device I got has 8 ports and PoE support (that I'm sure of) so it's more likely a SG2210P than a SG105E

  @Kosken 

Have you checked the IPaddress of the switch? I feel like you actually have two tplink switches and just login to wrong switch.

To confirm that, you can unplug this 2210P from the router, and only connect a PC to this switch. Set up static IP on the PC and login the siwtch via 192.168.0.1

  @Somnus thanks for trying to help. Unfortunately I only have one TP-Link device in the whole house and it's this one. Also, it's the IP that popped up in my router when I connected the switch so I'm pretty sure it's the right one. 

Unfortunately I don't have any computer with a network port, I only have light weight laptops running on Wifi.

  @crrodriguez now I've been up on the attic and as you can see from the pictures it should be a SG-2210P

  @Kosken The documentation says the TL-SG105E version 4 is an unmanaged switch.. maybe there is still a device confusion or a regional messup with the product naming, because unless they share basic software it cannot work with that firmware can it ?

maybe @Fae can shed light on this confusion- 

  @crrodriguez I agree that it seems very strange. As you say, the TL-SG105E is unmanaged so I wonder why I'm even able to access a webinterface. But the interface is a bit messed up showing the wrong number of ports and that wrong ports are connected.

  @Kosken  maybe the  tl-sg2210p was forced flashed something ? weird, you can probably restore the original firmware by booting the other partition (does it have a boot image selector?) you could in theory also upload the real firmware via tftp recovery.. 

@crrodriguez @Somnus this was really embarrasing. It was actually as you said Somnus, I DO have another TP-link device, a TL-SG105E and that's the one I've logged into. I noticed it because I disconnected the SG2210P and I was still able to access the webinterface.

Huge thanks for your efforts and sorry for wasting your time on something I should've figured out without posting here :) 

  @Kosken well ..the actual sg05e v4 latest firmware was released in 2018,  SG2210P v1 in 2016.. I do not know if later versions' firmware can be used with that device.

It is actually a very common confusion in the modern home  that's why centralized managment and inventory is important..imagine you get confused at home..try an small business