i dun think so...u can sell immediately i think...
ur relative maybe telling u about the loan...yeah, the loan got certain lockedperiod to avoid u to refinance or change bank.... maybe need to pay some penalty only....5% perhaps

I try before the bank lepas me from penalty despite the lock-up period because I sold the property.
The manager say if i refinance then they will make u pay penalty

One more issue, since it is a medium cost house, strictly speaking, the land title is classified as low cost.
There may be a restriction on sale of property subject to consent of state authority before it can be sold.
Most states uses a policy of not considering any application for sub sale if the buyer has not held the property for 5 yrs or more.

what is said above is correct, you can sell anytime, its just a matter of whether you are making a profit / loss after you sold the property. You can check your lock in period from the loan agreement you signed with your bank. You might also want to check your outstanding amount with the bank so that you can have a rough indication of how much money you will be able to take back after selling your property.
wow, can let me know which bank let you go from the penalty ?  and most important, how you managed to convince them ?