Krdytkyu

I'm looking for a word or phrase to describe when someone copies something down incorrectly.

Specifically, the situation I am thinking about is when someone is solving a problem (using pencil and paper), and in one step, they incorrectly copy an equation or expression from their previous step:

Joe Smith got 1 point off on his math homework for a ____ [error] when
he accidentally changed a 7 to a 1.

I originally arrived at the phrase "typographical error", however when I looked this up it seemed to only apply in the case of printing or typing (as in using a keyboard or typewriter), and does not seem to apply when writing with pencil, nor does it quite convey an issue with copying from a previous step.

Is there a more appropriate phrase that I can use?

EDIT: I'm specifically looking for a noun (or noun phrase) that can be used in the same way that "typographical error" is used.

I immediately thought of typo but that doesn't include the possibility that Joe incorrectly believed it was a 1 that he saw—and so deliberately recorded it as such.

A more appropriate word is mistranscription.

[Merriam-Webster]

: a mistake in transcription : an incorrect copy

// an unlikely word that was probably a mistranscription

And from Merriam-Webster's definition of transcribe itself:

1 a : to make a written copy of
b : to make a copy of (dictated or recorded matter) in longhand or on a machine (such as a typewriter)
c : to paraphrase or summarize in writing
d : write down, record

You can use miscopy:

to copy incorrectly:

• to miscopy an address.

(Dictionary.com)

Miscopy is also a noun meaning: an incorrect copy

From A Companion to Paleopathology 2016:

It might have been a genuine word of the time, or a miscopy of the manuscript due to scruffy handwriting.

From The Greig-Duncan folk song collection :

"Heary peary" at 1 1 .3 is probably a miscopy of "Heavy heavy".

and from
Handbook of American Indians North of Mexico:

The designation of this mission as “Purísima Concepción de los Asinais'' came from a miscopy of the word “ Ainai'' in Mem. de Nueva España, xxv II, fol. 163

(a) miscopying (of s.t.)

Censorinus wrote that Aristarchus of Samos reckoned a Great Year of 2484 years: it has been argued that this is a miscopying of 2434, which represents 45 Exeligmos cycles. (emphasis mine)
^{"Great Year -- Description", WP}

"(A) miscopying (of s.t.)" is already in regular use in genetics.

Joe Smith got 1 point off on his math homework for a miscopying when he accidentally changed a 7 to a 1.

I'd have loved miscopyment but it seems it's only the copyright attorneys who use the term copyment.

Writer hereby specifically reserves to herself those parts of the copyment that do not concem musical compositions or parts of musical compositions written by the songwriter … (emphasis mine)
^{("Hastings communications and entertainment law journal, XVIII, p.151," GoogleBooks)}