Retainer did not respond

Time: Permanent
Frequency: Permanent
World name: Gilgamesh
Character name: Chito Burrito
Retainer name: "Kimiko'chan", "Sekimino"
NPC name: N/A
Monster name: N/A
Class/Level: Doesnt matter
Party or solo: Doesnt matter
In-game time: Permanent, therefore, doesnt matter
Area and coordinates: Every area with a summoning bell
Housing: Doesnt matter
Steps:
1. Go to "Summoning Bell"
2. Try selecting one of my retainers I listed, "Kimiko'chan", "Sekimino"
3. Right after, a message appears "Your retainer did not respond"
4. The message disappears, and I'm back in my retainer selection

I cant use those retainers anymore.

Connection Specs
- Type of internet connection/provider: Doesnt matter, happens everywhere I try to open those specific retainers
- Modem maker/model number: Doesnt matter

PC Specs
-=-=-=-=- System Information -=-=-=-=-

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Laptop Model Name: Selfbuild PC
Laptop Model Number: Selfbuild PC

Specs:
CPU: AMD FX(tm)-6350 Six-Core Processor
MBO: ASUS Crosshair V Formula-Z, 990FX
GPU: Gainward GeForce GTX 780Ti Phantom
RAM: 16GB Corsair Vengeance Dual-Kit DDR3-1866 CL10 low
HDD: 1TB Western Digital Caviar Black, 1003FZEX, SATA 3
PSU: 850W BeQuiet! Dark Power Pro P10
Screen: LG 29UM58-P

Browser Information
- Name and version of the browser currently in-use: Chrome

Are these 2 additional retainers outside of the 2 free ones? If you paid your sub with a game time card or changed the card for your recurring sub you have to choose the retainer service again and pay seperately.

The retainers are active. I resubbed the slots just a few days ago. I have 8 retainers. Every each of them works just fine, besides those both.
If you don't have active slots, you get a different message and it shows next to the retainer name that they are not active. Thats not the case here :/

That is one wierd error and one certainly worthy of contacting tech support for.
Sounds like they crashed somehow. Do you remember when you last accessed them? Where you accessing them when you dc'd? I remember retainers having that bug once, where if you entered a duty while a retainer window was open led you to be unable to access them again.

Perhaps they are too busy lounging in a beach though. You'll need to punish them (on a less serious note)