Why is it that my battery cut down for 100% to 69%

Do you mean battery health has reduced to 69%? If you do, you have an old iPhone and if your iPhone has the original battery in it, it is failing as one would fully expect. You can pay Apple to replace the battery in your iPhone, but honestly, I wouldn't invest in such an old out of date iPhone. It would be a better investment to retire your iPhone in favor of a newer, more modern iPhone.

Are you talking about your battery health under Settings>Battery>Battery Health? If so, how old is your phone? Is this the original battery? If so, it probably needs to be replaced. Batteries are consumables. The eventually wear out.

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