Lyk

I would like to know Flexible benefits such as pension, dental insurance, private medical insurance...via salary sacrifice, do I need to report those contributions on self assessment (if no P11D from employment)? Do I need to pay tax on those contributions?

I received a refund about 800 pounds as paid too much tax, do I need to fill the refund amount in "Tax refund or set off - 1. If you've had any 2021-22 income tax refund or set off by us or..." in page TR6 on my SA100 ? Please advise, thanks.