Acrobat Pro DC - signatures not working anymore

[Paule15D5]

Since shortly, I am unable to sign any of my pdf's.

This worked fine previously while using my Isabel identification card to sign and lock our invoices.

Now, when I try to certify the pdf or digitally sign, the screen greys out and nothing happens.

Even with my e-ID it doesn't work anymore. Only hitting Esc (repeatedly) brings me back to the pdf.

At first I thought it was linked to my remote connection, but the problem also occurs in the office.

Thank you for your help.

[DWDU384973188giu]

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