Pencard

My daughter in USA. She dont pay tax in India. She is green card holder. She has rental income & invest in Icici prudential now. She invest in UTI Pension Plan. Her bank account closed after she came to USA. UTI require pencard to change bank account Please advise what she do. She paid tax in usa on rupee income. She has NRE & NRO ACCOUNT with Icici bank. She can apply online for pencard. If she become citizen what happened to her bank account. She should file nil return in india. She has active pancard and filed return when she is in india but pencard not traceable now.