Unfair dismissal

Mine is very heart breaking because I'm questioning the way pep store operates.. My wife was working for pep store in tembisa as a casual work up until they decided to employ her permanently.They gave her a company number and all and she was working with this so-called manager by the name of osman... To cut the story short my wife went to metenity 2018 and gave birth on 28 march 2018 and after the metenity leave was over she was supposed to go back to work but to my suprise all the pep store around tembisa said they dnt have space for bt they will call her when they have space...Now the thing is how come pep says they dnt have space for but we are seeing new people hired by pep and to make matters worse when she went to the shopto ask the manager to sign her papers from labour department no one was willing to assist her. So my question is... HR department since you are the ones issuing company numbers or perusal numbers to employees did ever asked what happened to this person or its how you operator by not caring.