Automatically log out

My phone suddenly restarts and all of my data are gone when I checked the discord app, my account is log out 😕 but my Facebook and messenger isn't…. I want to get my old account back the username is matthew_james. Please can anyone help me to get it back, that account holds so many memories…. And some very important Convos that's the only memory I had of my friend… the person is very special and mostly plays the most important role in my life…. I tried all of the things to get it back but I couldn't find any answers… even discord support can't help me.

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