Assalam Alaikum,
In the name of Allah the Beneficent the Merciful Peace, blessings and mercy of Allah be upon you. Is it acceptable to work in a bank`s call center (answering customer calls and provide them with services)? The employer is the bank. Jazakum Allah Khairan

Working in any conventional bank is not allowed, since it is an explicit participation in conducting-or facilitating- usurious transaction, where a Muslim should avoid it completely.