PAYE should be operated as
1) there is a UK branch
2) The staff are living and working in the UK
You should get this rectified as a matter of urgency. I have added the contact details here to arrange setting up a PAYE scheme, so that tax and National Insurance are deducted accordingly.
Do feel free to ask for any clarification on this, but it would be appreciated if you could rate the level of service I have provided or click accept, as this ensures I am paid.