SaaS supplier insisting we sign new terms

Bit of an odd one that hasn't happened to me before but just wondering if any of you who work directly with suppliers have seen similar?

We have SaaS provider and when we contracted with them our legal team renegotiated the terms of the agreement to clarify some details around data privacy. It was a long, drawn out process.

Recently the supplier has contacted us again and is asking us to sign their latest terms as there have been lots of changes. Are we obligated to do this? They have been very insistent and keep contacting us, but presumably we can stick to our current terms unless both sides agree to changes.

Their insistence makes me nervous that there is something in the new terms that benefits them and not us.

We've got a new legal team and just feels like it's going to be a massive PITA to go through this again.

Edit: you will all be happy to know that after sending a clarifying email to the vendor they have confirmed that they have actually including all original concessions and have sent a comparison summary with detials. Took me 5 minutes and has probably saved legal a tonne of legwork so all well and ends well.