Can't cancel tx

address: 0x512D7C3dEa407C3D559F3b9197061e130888E79c
just found i have a Tx in May, and I cant cancel this Tx.
when i try to find this Tx mainnet, it shows

Our low, medium and high estimates are not available.
Sorry, We are unable to locate this transaction Hash

Could you help me?
thanks a lot

problem solved.
go to My Account > Setting → Reset Account