As it’s sayimg 339% clogged, it’s worth considering that the DPF sensor may also be damaged.
Sometime if the filter becomes severely blocked the pressure I the DPF can build up to such an extent that it over pressures the sensor and damages it. That reading suggest to me that the sensor is damaged, I would probably disconnect the DPF sensors pipes, and reset everything and see if the pressure sensor is still reading 300+% blocked, if it is then you will at the very least need a new sensor.
Sometime if the filter becomes severely blocked the pressure I the DPF can build up to such an extent that it over pressures the sensor and damages it. That reading suggest to me that the sensor is damaged, I would probably disconnect the DPF sensors pipes, and reset everything and see if the pressure sensor is still reading 300+% blocked, if it is then you will at the very least need a new sensor.