It sounds to me taking into consideration this and your other thread that you might have gotten into the habit of "spacing out" during meditation. Calm spaciousness might feel like a sign of progress in meditation, and it usually is, but it needs to be accompanied by an increased sense of alertness, lucidity, immediacy if not then you're just wallowing in a feeling. This then makes going back to a technique oriented meditation like watching the breath difficult.
You are probably best to talk it through with a teacher.
In the mean time I'd recommend you get very specific about doing a very technique oriented practice like counting the breath for a full first half of your sitting, then followed by opening it up to a spacious awareness in the second half. Be careful to anchor your awareness in the body and what you experience through the six sense doors rather than just the pleasant calm spacious feeling. See if you notice a difference in the quality of awareness compared with what you werre doing previously, look for signs of craving or aversion just notice them and let them go.
"Right effort is effort with wisdom. Because where there is wisdom, there is interest. The desire to know something is wisdom at work. Being mindful is not difficult. But it’s difficult to be continuously aware. For that you need right effort. But it does not require a great deal of energy. It’s relaxed perseverance in reminding yourself to be aware. When you are aware, wisdom unfolds naturally, and there is still more interest." - Sayadaw U Tejaniya