Is there any literary name attributed to 12 verse length stanza?

Not a 12 line poem, but a 12 verse stanza.

There isn't a set name for a 12-line stanza that serves as the counterpart of quatrain (4-line stanza) or octet (8-line stanza, often used to refer to first eight lines of a sonnet).

The closest you would get would be the French term douzaine, occasionally applied by scholars describing a specific medieval French stanza form. This term is highly specialized and not really used in English:

One potential influence on stanza-length may be a twelve-line stanza popular in French literature from the twelfth century onwards and known either as the douzaine (for obvious reasons) or the strophe helinandienne [...] (Rhiannon Purdie, Anglicizing Romance: Tail Rhyme and Genre in Medieval English Literature, 2008).

There are English poems with multiple twelve-line stanzas though, like the late 14th-century poem Pearl. Critics commenting on these stanzas plainly call them twelve-line stanzas or use similar phrasing:

[The second York play] is in twelve-line stanzas, of which the first eight are octosyllables, rhyming alternately, the last sixes maintaining the even rhyme but importing a new odd. (George Saintsbury, A History of English Prosody: From the Origins to Spenser, 1923).

Fein, Susanna Greer. “Twelve-Line Stanza Forms in Middle English and the Date of Pearl.” Speculum, vol. 72, no. 2, 1997, pp. 367–398. JSTOR.