With a set stock it depends on what orders or on the book and in TWT's case there is very little on the buy side of the book at anywhere near the offer price because to be quite frank very few people want to buy this share at this time.
Most market makers leave this stock the hell alone at this time because there is not enough volume to make it worth their whiles. You just need to take a look at the sizes of orders on the book pretty much any day of the week to realise that it's all sells on the offer side at the moment.
you could ask your broker to place your shares for sale on the order book in which case somebody may or may not buy them off you - not all brokers will do this for you mind you.