Thank you for your question. According to the school of Ahl al-Bayt (as) there is no problem with combining the zuhr and asr prayers in that sequence (one prayer immediately after the other or with any time gap between) after the time of zuhr has set in without any specific reason. Similarly there is no problem with combining magrib and isha prayers after the time of magrib. So there is no problem praying isha prayer after magrib prayer and before 7pm.
May you always be successful.