Why doesn't StackMap integration work in Discovery?

After setting up the configuration for StackMap in Service Configuration it does not work.

Navigate to OCLC Service Configuration > Third-Party Integrations > StackMap & follow these steps:

Check all settings including the domain name identifier are correct, as required for StackMap integration
When selecting the Holding codes to be used, ensure that only text has been used for these, with no symbols or special characters
If a Holding Code has any special characters displayed such as a semi-colon or colon, for example, Demo University: Library The integration will not work.
If you see these special characters or symbols in your Holding codes, these can be updated in Service Configuration > WorldCat Discovery and WorldCat Local > Holding Codes & Shelving Location Messages > Holding Codes Translation Table.

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