The type of exercise will dictate how many times you do it per day.
Why this matters:
When you’re following a pain relief program, every action should be focusing on one of three things: reducing/abolishing your pain, prevention, and correct movement.
You’ll notice the exercises designed to reduce your pain are actually able to in fact do its job within a few repetitions. Something like a backbend or a forward bend. If the exercise/movement reduces your pain, you should be doing them as often as possible. Especially when you have a flare up of symptoms.
Exercises to prevent pain are more stretches to prevent tightness and strengthening exercises to weaken inactive muscles. Examples include a glute bridge or a lunge. You can do these movements once a day.
The third set of exercises is correcting movement. Not only will you do these exercises once a day, but also think about doing them sitting/rising from a chair, or picking something up from the ground. Practice makes perfect.
Look at your current routine. Evaluate how often you’re doing it. Do you need to do them more or less?