Answer: What you describe sounds like normal summer weather damage and your mandevilla will overcome the damage and begin to grow again once the temperatures cool down a bit. Take your plant back outside and set it on the patio. You can prune away the damaged shoots and new growth will emerge when conditions are cooler. Don't water everyday unless the soil actually dries out on a daily basis. Regardless of the temperatures, plants can use just so much water and if you keep the soil saturated, you'll drive out the oxygen, which is also something the plant roots need. Stick your finger into the soil to check the moisture level. If it's dry one inch below the surface, it's time to water. If it's still moist, you can wait another day or two before watering.
Best wishes with your mandevilla!
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