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I am of Syrian nationality. I got a visa to Singapore through the Singapore consulate in Lebanon. I travelled there 28-6-2017. When I reached Singapore, the immigration officer asked me about my return ticket. I showed it to him, but unfortunately I didn't notice that the return date was more than 1 month. Also he asked for a hotel booking, but I didn't have one. For those reasons, he refused my entry. I was returned back on the same airline.
Is the visa still valid? If I prepare the requested documents and travel again, will I be banned? They didn't stamp my passport. They took a thumb print.