Yes. The Quran commands returning trusts to their owners (4:58) and forbids betraying them (8:27). This includes money left with you, secrets, and the duties of a job. Delaying payment of a debt when you are able to pay is also a form of injustice.
ऐ ईमानदारों ख़ुदा तुम्हें हुक्म देता है कि लोगों की अमानतें अमानत रखने वालों के हवाले कर दो और जब लोगों के बाहमी झगड़ों का फैसला करने लगो तो इन्साफ़ से फैसला करो (ख़ुदा तुमको) इसकी क्या ही अच्छी नसीहत करता है इसमें तो शक नहीं कि ख़ुदा सबकी सुनता है (और सब कुछ) देखता है
ऐ ईमानदारों न तो ख़ुदा और रसूल की (अमानत में) ख्यानत करो और न अपनी अमानतों में ख्यानत करो हालॉकि समझते बूझते हो
This is general information, not a fatwa. For your own situation, ask a qualified scholar.
Questions about halal and haram
Is it haram to betray a trust?
Yes. The Quran commands returning trusts to their owners (4:58) and forbids betraying them (8:27). This includes money left with you, secrets, and the duties of a job. Delaying payment of a debt when you are able to pay is also a form of injustice.