With signature as "read only" marked fields can now be changed in Acrobat Reader Version 18.10.02 on iPad

Hello all,
I created a form with Acrobat DC and added some data fields as "mark as read only" to a signature field.
Until latest Version of Reader it worked well on the iPad when using the form.
Now after update on iPad to Reader Version 18.10.02, the marked fields can now be changed even when signature is already done.

How was my workflow:
Form was created with Acrobat DC on Windows PC

Data fields filled and signature done with Reader DC on Windows PC

Marked as read only fields cannot be changed after signature, when using Reader DC on Windows PC

Marked as read only fields can be changed after signature, when using Reader 18.10.02 on the iPad.

Failure occured after update to Reader 18.10.02 on the iPad.

Need help to fix this problem.