Try calling any reservations number and ask for seat allocation. State that the ticket was ticketed Jan 14.

FROM SQ FAQs
My ticket on an Economy Lite fare was issued before 20 January 2018, but I have not selected a seat. Will I be able to select a seat in advance, now that the fare conditions have changed?

Yes, you will be able to select your seats in advance for free
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This means even the lowest fare class allows free seat allocation. Whats important is that the ticket/e-ticket was issued BEFORE Jan 20, having it reserved without it being confirmed before that date will mean application of the new fare rules.

I've made a booking before 20 January 2018 but will not ticket it until after. Can I still enjoy the old fare conditions?

Tickets issued before 20 January 2018 will be subject to the old fare conditions, while tickets issued on or after 20 January 2018 will be based on the new fare conditions. This means that if you only ticket your booking after 20 January 2018, the new fare conditions will apply


Also, maybe you encountered an IT but when they updated the sites.