The lesson about backups cannot be repeated enough. If everybody already new how important a backup is for ANY reason, not just ransomware, them you and the many others would not be posting here now.
By supporting the criminal activity (paying) you are not just taking a hot financially, you (collectively) are putting everyone at risk as hundreds of thousands of dollars can then be used to find new ways that could target us all.
You *DID* have an option, in fact, 2 options. Pay, or not pay. If your NAS had been stolen (or burnt up in a fire) you would have no options other than complete data loss.
I'm sorry if you feel embarrassed, but by talking about the problem and repeatedly educating people about the importance of backups against many different threats, others may learn *before* they get hit or run into other issues. The day people stop posting that they were hit by ransomware and had no backup is the day I will stop reminding people to have a backup against as many threats as possible. This is only ONE of MANY possible threats.
Lesson 1 - have a backup strategy that fits with your data
Lesson 2 - spend an hour reading about *ALL* the devices on your network and learn the basic steps to secure them. (At least sign up for security notices about vulnerabilities)
These lessons may not help you *today* (as there really is no help to be given since you either take the data loss, or restore from backup, or pay the ransom) but they are critical for the day you get your system running again either from a complete reset or from decryption. If you don't learn these lessons, you are still vulnerable. Whatever you did to allow the attack should be resolved now, before anything else or there is no point.
We are trying to help you, so that you aren't back in the same situation in 3 months.