Security of personal data when using email link to infusionsoft hosted webform

I am using a i/soft hosted webform to allow my contacts in the uK to look at the data we are holding on them - a GDPR issue and a way to check what we have is correct.
We have had some contacts come back and say that although it is their data in the webform, it is unsecured via the link in the email AND on the webform.

I know that when the link is clicked from the email account that matches the email address used and the first name or last name are the same as the isoft record that it then mirrors the data into the various fields.
What other security do we have that I can share with them?
Thanks

Have they provided to you any specific security concerns? Providing a link in the email builder to a hosted web form doesn’t expose any PID. The only risk I can think of would be if they forwarded the email they received from you to a random stranger that now has a link to view their PID.

Hi Martinc,
No nothing specific - the members are from the UK where there is a hugh drama and lots of security scares following the introduction of GDPR. legislation.
This is a situation where the fear and hysteira is all based around “what if …happened” speculation.
I was hoping to get a good technical answer i can use to say - your info is safe in a link in an email - … any chance you can give me one of those?
Glad to hear that my understanding that the information is safe is correct.
thanks