Hi Ana Ana,
If you need your P45 to update your new employer, contact us by webchat or phone here:
Income Tax: general enquiries
If your previous employer has updated your pay and tax electronically, as they're obliged to, we may now have received your final pay and tax figures from them.
We can then update and issue your code for your new employer
If you require your physical P45 for some other reason, and your employer continues to refuse to provide you with it, write to us to confirm this at Pay As You Earn and Self Assessment,
HMRC,
BX9 1AS.
Thank you.