Put dimensions and constraints in the sketch and use same thickness in the whole sketch.
Also be sure to enter sheet metal rules for the thickness of your sheet.
As indicated - Your sketch is not constrained - read this
Your part is not uniform thickness, but sheet metal requirement is uniform thickness.
Problem 3 you used Extrude rather than sheet metal tools?
Problem 4 - you are doing too much work, get lazy.
Edit Sketch1 and notice only one side open profile needed.
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