Excuse me, if you write a debit note, affix a special financial seal and sign it, but the other party keeps a copy, can this form legal liability?
Any copy is legally invalid. So that the copied materials have legal effect. The sender should indicate on the copy that this copy is the same as the original. Stamp with official seal, head seal and signature of the agent. This copy has the same legal effect as the original. You said that the other party only has a copy, which cannot form legal responsibility. Because the other hand is actually just a blank piece of paper with no legal effect.