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I am a USA female citizen.
I travelled as a tourist to Singapore several times, never overstayed, but I did usually stay nearly the maximum 90 days.
I have OCD and wash everything.
One time I got rejected when I tried to enter Singapore with a damp passport because I was told it was not in good condition.
I know that sounds stupid to present a damp passport but it gets worse ... also I got quite upset because I was being deported all the way back to USA and I did not want to go back. It was a business class ticket on Singapore airlines and the airline was responsible to pay for my return so they did not like that and subsequently banned me.
I did get accepted back into Singapore as a tourist a year or so later, but had a few weird problems like getting caught for taking a shower at a resort swimming pool facility where I did not stay.
I had to leave Singapore in an odd way, with my passport held at the airport.
I had to collect it with a special letter on the day of my flight.
I tried to go back again to Singapore about a year after with a good quality passport but was refused for "secret reasons". The officer did mention to not try again for at least 6 months.
I love Singapore because it is tropical and clean.
I am not a criminal but my odd OCD behavior seems to have caused a problem with visiting. I spend a lot of time in Thailand by the way and of course immigration there is different.
Any suggestions how I can get another chance with Singapore? I think I have learned my lesson about how to behave there and hope it is not too late.