Change a will after no change stipulation

Location: Texas

My wife and I made a will about 16 years ago. We stated that the other was the beneficiary upon one of us passing. We also stated that the will could only be changed if both of us were alive to make the changes.

My wife passed away 13 years ago and some things in my life have changed during that time. I would like to make some changes to the will but not sure if I can create a new will.

Any legal advice would be appreciated.