Is my SIPP "registered with HMRC"?

so I have paid some cash into my SIPP and now a few years later want to claim some tax back from the HMRC. Yes Freetrade automatically apply 20%, but that means I should still be able to claim some back.

However - on the HMRC website it makes it clear:

“You cannot claim tax relief if your pension scheme is not registered with HMRC.”

…but is it??? - how would I know? Anyone enlighten me here?

You are already receiving tax relief. If wasn’t registered, you wouldn’t be receiving the tax relief payments in the SIPP to begin with.

Yes it is, otherwise you’d be getting no tax relief paid into your SIPP. I take it you’re a higher or additional rate tax payer and wish to claim the additional tax relief to which you’re entitled by way of a Self Assessment claim. I’ve done it the past couple of years, no problem.