Multiple signature workflow. Sign tool and Digital ID work differently.

I need some assistance.

I am creating an application for leave form that requires a two step signature. The form has two sections. Employees section and admin sections. The employee fills the form first then submits to admin for approval.

Example:

The employees fill out the fields then signs and submits the form. When the form is submitted. the employees fields must become read only and the admin office section fields must remain open.

Once the admin office has approved the details the form must be signed and submitted to management.

The problem comes in when the employee signs the form. The form currently behaves differently depending on how the form is signed. If the form is signed with a digital ID then it works perfectly and makes the form read only for the employee section as desired. But, if the form is signed with the sign tool (fountain pen icon), then the entire form becomes read only when submitted.

I need the admin section entry fields to remain fillable when signed by both digital id and signature i.e I only need certain fields to become read only.

I have tried the field settings but like I have mentioned above, it only works as desired when signing with a digital ID.