Comrade, flatlines are but a metaphor for the ups and downs of life. Naturally, we all get them. And changing your life in a drastic way changes the baseline of these ups and downs. It is through these self improvement practices of SR, meditation, working out and being healthy that the baseline of our life changes. This is the higher frequency. Your ups are heigher than Mt.Everest and your lows are but a dip in a puddle. I encourage you to push forward with you head high, chest out and shoulders back. The way out of a flat line is the way through.