Unthawed chicken breasts will take longer to cook in water than thawed ones due to the fact that frozen chicken breasts need to be thawed by the temperature of the water in the pot before they can be cooked, so it will take longer accordingly. If the situation is not particularly urgent, you can do the following:

Take the chicken breasts out of the refrigerator before you prepare to cook them, and let them thaw naturally outside in the ambient temperature.

Place the thawed chicken breasts in a pot, pour in the appropriate amount of water, add your favorite seasonings, and turn up the heat to start cooking.

When the water in the pot comes to a boil, turn down the heat until the water in the pot comes to a boil.

Waiting a little time to cook to half-cooked, the lid will be open, the fire slightly increased, collect some juice until cooked, this way to cook the chicken breasts than the kind of direct not thawed in the pot to cook the texture is good.