labour the point

labour the point (to try too hard or continue to describe or explain sth or express an idea, feeling or opinion in too much detail after everyone has clearly understood it (repeating it unnecessarily or adding more details) — вдаваться в чрезмерно подробные объяснения или рассуждения; (чересчур подробно или тщательно) вникать в детали, мелочи; пережевывать одно и то же ; закцикливаться, застревать на деталях, подробностях, копаться в чем-л. (в см. повтороять одно и то же); (продолжать) разглагольствовать

Example 1: Look, I understand what you’re saying — there’s no need to labour the point.

Example 2: Sorry to have laboured the point .

Example 3: Restlessness or inattention on a general scale suggests the teacher is either labouring the point too much or that the material is too difficult or too easy. (Brian Seaton, "A handbook of English Language Teaching terms and practice", 1982)

Example 4: . "I'm sorry." Luke frowned, went over to the coffee-machine and poured two cups, placing one in front of Merrill. "I don't want to labour the point ," he said softly, "but I still don't understand why the secrecy." ( Kate Kingston, "A warning of magic")

Related vocabulary:
keep on,
go on,
hold forth,
... more
...
уши прожужжать

Cf.:
[nitpick]
[split hairs]
[pick holes in sth]
make too fine a point
[цeпляться к мелочам]