This study aims to design a dynamic model to assess the potential impact of CBDC issuance on banking system stability. The study results show that overconfidence of economic agents towards CBDCs can drastically reduce bank reserves, thereby limiting the lending capacity of banks and creating liquidity problems. Similarly, increasing reserve requirements in fiat currency for each unit of CBDC issued can constrain bank reserves and restrict loans and deposits. Additionally, a rise in interest rates on CBDC-related loans can discourage borrowers, thereby reducing loan demand and affecting banking activity. An increase in interest rates leads to a decrease in the quantity of CBDC in circulation, an increase in bank reserves and deposits in CBDC, and a decrease in bank loans. Monitoring the level of confidence of economic agents towards CBDCs is crucial to avoid excessive speculation.