Seems that there should be a screenshot in your question, but there is none. And I assume that you receive "Selected address cannot be found due to the web mapping service error" error message and it is related to the fact that https://nominatim.openstreetmap.org service that is used in maps cannot find address you've specified (for example because of ZIP/Postal code). Please remove Postal code from your address and check the issue once again. Also please check if your address can be found in https://nominatim.openstreetmap.org.
I have the same problem with the addresses in Brazil, and it works fine when I remove the Zip/Postal code. Is there any setup for that, so that I can keep address with the ZIP/Postal code and prevent the OpenStreeMap service from using it for the search?
Most likely, there is some issue either on the object level or DB level with the externalisation field (since removing it helped). Most likely it was renamed or the compilation didn't go successfully when adding it. To fix the issue you can try doing the following steps: Generate source code for all -> Compile all -> Update DB structure. If these steps won't help please contact the support team at support@creatio.com. The issue would be easier to analyze after seeing the full log as the message in the UI doesn't reflect where exactly the error occurred.