0xf56926f9ca9abc1065153d25383e80 is a 116-bit private key, which out of range for n. What's more, you're dividing it by -1 so it calculated -0xf56926f9ca9abc1065153d25383e80 instead. This is still not in range, so it'll keep adding N (2^70 = 1??) to this number until it is within range, hence mod(-0xf56926f9ca9abc1065153d25383e80, n) = 20212ef8c52b3a842d0bc <-- this is a 70-bit private key.

When you attempt to make a public key it interprets the input as 256 bits. So if you want to avoid that, you must insert the modulus first.