Pelletstove troubleshooting

ood evening, I have a pellet stove, but when it operates, it accumulates residue in the burn basket by the end of the day.
I measured the air temperature with a thermal camera, and it shows around 115°C, while the glass temperature is approximately 260°C.
I have set the pellet loading period to 10.8 seconds and the pellet ON loading time to 1.2 seconds. The combustion air is at 2250 RPM, with a maximum of 2500 RPM. I measured the pellets, and they have 8% moisture content.
The flame is short but very intensive, the exhaust gases have 220 Celsius. I have a phi30mm pipe 3 meters long for fresh air input, according to calculations approximately 366 liters of air per second can be pumped, I think it’s ok. With this settings I don’t have burned residues but if I give more pellet, because it’s cold now, then accumulating residues very quickly.

Do you have any ideas on how to prevent residue from accumulating in the burn basket?