Undervaluation relative to MRP: detention solely on that basis prohibited; procedural verification and reporting required before action. Detention of goods in transit solely because invoice value is below MRP is impermissible; intelligence squads must not detain or issue show cause notices on that sole ground. Suspected undervaluation must be recorded by uploading invoice details via the Mobile App and reporting to the jurisdictional officer and district Joint Commissioner. Intelligence squads must collect documentary evidence of actual supply value and classification, after which the jurisdictional officer shall verify and then take any further action as provided by law.