Cannot read openAPI spec

[Swap3093]

getting the below error:

Exception in thread "main" java.lang.RuntimeException: Cannot read old openAPI spec at org.openapitools.openapidiff.core.openapicompare.notnull(OpenApiCompare.java.105)

[Swap3093]

While trying to compare or compatibility check two yaml file

[joschi]

[…] and provide as much information as possible, such as the exact version of openapi-diff you're using and the OpenAPI specs which cause the issue.

#182 (comment)