Answer:
"We are here to help, Nina? Our Support Team is just a Click away".
Step-by-step explanation:
As Nina is the returning customer, we should know her concerns that why she left visiting our website, did she face any problem, was she not happy with our website or what really and exactly the reason could be, therefore, message should base upon helping her and her guidance. We should direct her to talk to our team (from support department or customer care department), whether she is in need of any help. In this way, someone talking to her personally, can definitely gauge the reason and extent of the problem, therefore, the best message should be read as:
"We are here to help, Nina? Our Support Team is just a Click away".