Put the warning in the tuning history
Tell us when the remap was installed, whether hardware changed afterwards and when the DPF message first appeared. That timeline helps scope the investigation; it does not establish that the calibration caused the fault.
Keep the earlier findings
Send the complete diagnostic report and any filter cleaning, sensor or engine repair invoices. If the car has been returned to a different calibration, include that detail too. Say what changed after each job.
Choose investigation before another tune
A filter warning is not a reason to select a more powerful file. The workshop can discuss the checks appropriate to the actual engine and system. Once the current concern is understood, a separate tuning recommendation can be considered.
The previous-remap guide helps organise unknown software, fitted parts and current symptoms. Send the history before reserving workshop time.
Mobile Stage 1 and ECU solutions, or workshop chassis dyno tuning