Does the construction "not only … but also" require a comma? I can't think of any punctuation rule that says there should be a comma there. Is there any?
Your example sentence does not require a comma - its pretty straightforward (although the sentence has other problems).
"There is no standing rule requiring writers to split up a "not only ... but also ..." construction with a comma ..." – Sven Yargs (ELU) in ... do commas belong in a “not only… but” sentence ...?
"I'd say a comma is never 'needed' here, and best omitted unless length of the correlates makes understanding difficult." – Edwin Ashworth (in same ELU question linked above)
"Not only those people who never seem to be able to make up their minds which way to vote until the very last minute, but also those who in the recent past have remained faithful to their traditional parties, are deciding that this election is one where they must examine the party manifestos very closely."
"Not only the Smiths but also the Browns were really taking the quiz seriously." – Edwin Ashworth
Also see Cambridge Dictionary Not only … but also
Also remember to check what your style guide says about such things (look for punctuation with correlative conjunctions).
The Chicago Manual of Style (17th Ed) says in 6.46: Commas with “not . . . but,” “not only . . . but also,” and the like
With an interjected phrase of the type not . . . but or not only . . . but also, commas are usually unnecessary.
- "They marched to Washington not only armed with petitions and determined to get their senators’ attention but also hoping to demonstrate their solidarity with one another."
If, however, such a phrase seems to require special emphasis or clarification (usually a matter of editorial judgment), commas may be used to set off the not phrase. Alternatively, a dash may be used in place of the first comma, in which case a second comma usually becomes unnecessary.
- "She was in the habit of placing her orders months ahead of the competition—not only as a matter of personal pride but also to bolster her credibility as an early adopter."
Usage of not only . . . but also (without comma) in 5.199: Correlative conjunctions
- "they not only read the book but also saw the movie"