My friends son did this on a truly horrendous call from her boss where he actually threatened her if she didn't take on yet more work, during Covid.
I heard the call afterwards.
Her son had called to the house.
It was a friday afternoon and she got signed off work monday morning.
She raised a grievance and did a word for word document which stated her son had the recording and wanted to involve the police.
She was off work for 9 months on full pay.
She now works from home only, 3 days a week on the same pay.
She has the receipts having worked there for 15 years.
This is a household name company.
She laid out in her grievance the bullshit she has tolerated and name check half the board.
They tried to offer her a severence but she point blank refused it and made it very clear it will go to tribunal or court.
The prick is still employed but on the one occasion the accidentally bumped into each other he bent himself out of shape telling her how fabulous she looked.
For 15 years she kept those receipts....emails upon emails of shocking stuff and very careful note taking.
It has served her so well.
Her excellent legal emplyment specialist told her that her notes were peerless.
Start looking back and creating notes, a timeline of the bullying.
If you can record, do it.
Call ACAS for specific step by step advice.
Your union 100% should be your first call, with your notes of examples, dates, any witnesses etc.
Go to your GP and get signed off.
Spend that time writing up the grievance and looking for another job.
Decide then if you wish to go ahead with the grievance.