Stupid mistake in leasehold flat - pet

[Cinnamontoas]

Please help!
I've made a really silly mistake on a flat I rent out (my previous home before I met my husband).
I mistakenly said the tenants could have a pet, thinking it was allowed in the lease and now it turns out it isn't allowed under the lease and the freeholder won't give permission (even though other flats in the block do have permission)
I feel absolutely awful, I'm a pet lover myself and I'm so upset/cross with myself for putting the tenants in this situation.
Is there anything I can do?

The Government website has a page about this
https://www.gov.uk/guidance/renting-with-pets-renters-reform-bill
This bill (not yet passed) suggests landlords must have a reasonable excuse not to allow pets. There is the option of the tenants taking out comprehensive insurance, which might reassure the freeholder? If other leaseholders are keeping pets though, it seems unreasonable to refuse your tenants. Good luck!

Thank you so much for your reply, it's really helpful!

thinking it was allowed in the lease and now it turns out it isn't allowed under the lease and the freeholder won't give permission (even though other flats in the block do have permission)

Do you know for certain they were given permission? Has the leaseholder themselves told you they gave permission?

I asked to have a pet in a rental a year or two ago. My LL, the leaseholder, said no 'for many reasons' which he didn't elaborate on. He was shocked when I told him there are other pets in the building. I assume one of the many reasons was he didn't allow pets fullstop, so he couldn't start with me.

It came to light because there was an issue with my tenants pet and another pet in the block, so it is an assu. Orion but I would have assumed it would have come out in the conversation.

I'm just thinking now that I should email the freeholder, explain it was an innocent mistake and ask him to grant a temporary pet license for the next couple of months and just hope, hope, hope