Statement of tax liability - The Netherlands requested 3 months ago

Hello, I have been asked by my Dutch pension provider to provide to them a Statement of Tax Liability. I am told that the UK has the right to claim tax on a foreign pension but in order to do this, need to have confirmation that I am a resident UK tax payer. I requested this 3 months ago via my accountant who sent HMRC the relevant paperwork (just one page to sign) I am still yet to receive it back and am understandably being chased by the Dutch authorities. What lead time is realistic to receive such documents back please? Should I resend it to you? Many thanks in advance for your advice.

Hi
You can progress chase your request for a certificate of residence, either by contacting our webchat facility at Self Assessment: general enquiries or by telephoning our self assessment helpline 0300 200 3310.  If you need to resubmit a certificate of residence request, you can do this online at
Self Assessment: general enquiries