In DHL, DTP is a synonym of DDP:
Delivered Duty Paid (DDP)
Commonly referred to as Duties and Taxes Paid (DTP) at DHL Express.
Selecting this option indicates that the shipper or account holder incurs the full costs of the shipment, including any duties or taxes that might be incurred from customs.
dhl.com/discover/en-sg/logistics-advice/incoterms-2020
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If the incoterms mentioned on the airway bill document are DDP or DTP, or if it is marked that the consignor will be charged for the customs clearance taxes, duties and fees; mentioned expenses can be paid by the consignor if the clearance processes is being held by a DHL authorized customs brokerage.