Showing us a single line of input and a single line of output while talking about multiple occurrences of a pattern that may repeat on multiple lines leaves a lot to the imagination.

Do you just want to change ABC for A to row for a as shown in your example? Are there other strings that you want to change? Can these three word sequences appear multiple times on a single line? Can these three words be split across lines for a singe occurrence?

What operating system are you using? Are we restricted to a certain shell or set of tools to be used to solve this problem?

For what you have shown us, the much simpler command:

Code:

sed 's/Locking.*Access/Locking row for access/'

does everything you've shown us needs to be done.