Thank you for providing details of your situation, it's very helpful for me to figure out what's going on, and what the solution is. Sorry for not responding sooner, I was working with a print client all last week, so wasn't at my computer as much as normal.
Based on your order history, I see you started using refillable cartridges and Piezography Neutral ink around July of this year. I also quickly read thru our past emails, and see you have replaced the set of dampers, wiper blade and cap pump assembly- correct? Did you also replace the flushing box? If not, it would be best to install a new flushing box and clean out the tube (you can rinse out and reuse the current tube, as long as it's not broken), since you have replaced the other cleaning area parts.
I don't suggest replacing the wiper blade and capping station again, and instead think it's best to look elsewhere for your solution, as these two parts were recently replaced and are likely not causing your current issue.
What is the temperature and humidity in your printing environment? Going into the dry winter months, humidity is a big issue now, as dry air can easily cause flow issues and clogging. We follow the industry standard by monitoring and maintaining humidity levels between 40-60% in our print areas, and try to never print below 35%.
Please let me know so I can help you get past this and back to happily printing.
Best regards~ Dana