He has two wives and it is difficult for him to treat them fairly
Question

                A man has two wives, each of whom lives far from the other, so it is not easy for him to treat them equally in terms of staying overnight with them. His place or work and business is where one of the wives lives, which means that he spends more time with one of them than the other. Is this husband sinning or not?.
Praise be to Allah.We should see whether 
    the two wives are happy with the situation or not. If they are both happy 
    then the matter is clear, because they have the right; if they are happy 
    with what the husband is doing then there is no problem. If each of them 
    demands her rights for the situation to be corrected, then he must treat 
    them equally, spending a day with one and a day with the other. If it is too 
    hard for him to go back and forth between them every day, then he may stay 
    with one for three days or a week, and with the other for three days or a 
    week, according to whatever he agrees with them. What matters is that he 
    should treat them equally in terms of maintenance and time and everything in 
    which he can treat them equally. 

    Shaykh Ibn ‘Uthaymeen. 

    Liqaa’aat al-Baab il-Maftoohah, 
    3/447 

    He should try to make their homes closer together and nearer 
    to his place of work and business, so that he will be able to treat them 
    fairly. 

    And Allaah knows best.