S5 Neo not getting texts from LG G3

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AC Question

I just got my new phone s5 neo and my son got lg g3,I receive texts from other friends and family except him.I thought it was a proximity thing because when he was beside me it wouldn't come in but when he was outside I got his texts.Now he is trying to text me and gets my texts but I do not get his.HELP please and thanks
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