3458444 - Digital signature stops generation for the cloud system

When trying to print the billing document below error message raised:

• Item '1': Rendering of document started.
• Item '1': Rendering of document via service ADS failed.
• Messages have been generated during form rendering.
• Error when extracting data of entity
• Print Character not assigned for billing document &

• SAP S/4HANA Cloud Public Edition

1. Open app 'Display Billing Documents'
2. Enter billing document number -> Click Continue
3. Go to 'Display output requests'
4. Select print output
5. Click on 'Display document' (F5)
6. Error message displays

Digital Signature Apps for Portugal >> Maintain Document Number Gaps and Generate Digital Signature for Billing Documents(Maintain SD Document Number Gaps).

Due to gaps exist in the sequence of any of the billing documents, so not able to create a digital signatures for the billing documents.

As per PT legal requirement, a billing document without digital signature cannot be printed and the digital signature stops working if its previous billing document has no digital signature (except for the very first billing document).

To solve this issue it is required to maintain that missing billing documents in to GAPS>>Maintain SD Document Number Gaps - Portugal app 

Example:
If the billing document 10001 is missing (or) not having the digital signature and try to print the billing document 10002 then system will not allow to print the billing document 10002.

For more information to maintain entries in GAPS, Maintain SD Document Number Gaps - Portugal.
https://help.sap.com/docs/SAP_S4HANA_CLOUD/6dbc01446ae14a28b7142bb2203abc10/9b3390f14f7141d1af2c3c93bae7ad80.html?locale=en-US

Go through the Help Portal Link for Printing Billing Documents with Digital Signatures:
https://help.sap.com/docs/SAP_S4HANA_CLOUD/6dbc01446ae14a28b7142bb2203abc10/3029a05fbfe2402486f9d377a3e6ce6f.html?locale=en-US

Note:
In Portugal, it is legally required that billing documents are sequentially numbered with no gaps existing in the sequence.

• If using own layout For Example: YY1_XXXX, That means you are responsible, how they work.
• The gateway service FDP_V3_BD_STANDARD_GLO_PT_SRV, in standard we designed to use with our form template: SIPT_CI_SDBIL. It can be used this also with clones of the same.

3410151 - Completed output item without a stored document cannot be previewed - S/4HANA Cloud 

Help Portal Link Additional Fields Available in Output Form Template for Billing Documents in Portugal: 
https://help.sap.com/docs/SAP_S4HANA_CLOUD/ee9ee0ca4c3942068ea584d2f929b5b1/a191a80fb6484b94aba832e16c1f1a82.html?locale=en-US

Help Portal Link regarding the Maintain Document Number Gaps and Generate Digital Signature
https://help.sap.com/docs/SAP_S4HANA_CLOUD/6dbc01446ae14a28b7142bb2203abc10/1c6d0224fee84c5682ea5f342cb49d75.html?locale=en-US 

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