All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.
The uncovered credit card issued by the interest-based bank which includes terms and conditions that include interest is prohibited, and it is not permissible to deal with it whether by the person in whose name it is issued or by his agent (the employee here), as is the case in the question.
The decision of the Islamic Fiqh Academy (No. 108 / 2/12) states, “It is not permissible to issue a non-covered credit card or to deal with it if it is conditioned on interest, even if the card applicant is determined to repay it within the free grace period.”
For more benefit, please refer to fatwas 98959 and 88473.
Allah knows best.