Hopefully making theology simpler to understand! (2 Corinthians 1:12)

“‘And it shall come to pass that everyone who calls upon the name of the Lord shall be saved.'”
Acts 2:21, ESV

Calling on the name of the Lord is not merely praying or saying you understand or want something.
It is realizing you have been wrong and that Christ is the only way to be made right with God, believing He died for your sins, and trusting that He has indeed saved you and brought you into a saving, loving relationship.