Hi we are buying a resale flat, first time buyers. We side (buyer) has completed the submission process a day after the exercise but the seller side has not yet completed the submission. Should we worry after 4days of waiting? HDB website says submission will be invalid after 7days if either one does not submit. Our concern is that, do we need to worry why the seller doesn't do the submission yet? Is this something very hard to do or should they have a good reason of delaying the 1st appointment by not submitting?