With the surge in digital wallet usage across fintech platforms, secure and privacy-preserving Know Your Customer (KYC) mechanisms have become increasingly critical. This survey reviews the current state of digital identity verification frameworks, emphasizing the challenges posed by centralized KYC models, including data breaches, lack of user consent, and regulatory fragmentation. We systematically analyze more than 50 recent studies and industry practices addressing privacy-preserving identity protocols, decentralized identity (DID) systems, cryptographic techniques (such as zero-knowledge proofs), and access control architectures. The paper proposes a reference architecture reKYC based on common patterns found in the literature, integrating layered components for identity verification, access governance, trust evaluation, and regulatory compliance. We classify existing approaches by their trust model, cryptographic basis, and consent mechanisms. Key gaps identified include limited regulatory interoperability, weak user-centric control models, and lack of scalable trust frameworks. This survey concludes with open research directions and a future outlook for secure, privacy-aligned digital wallet verification.