I have a pink bikini changer cord when I change my i phone 8 se when it’s charging half other half not charging for any reason

i have bikini charger cord and when I changing

my i phone 8 se in my double outlet and my power Blocks half charging half not charging I have too more power Blocks and too charging cords it does the same thing half charging half not charging for any reason different stores i buy it at my phone company store and staples and Walmart and target when i buy it it works and doesn’t work after i test them out but my old phone i use to have i l did not have a cell phone at all on till now this my new i phone 8 se