Cannot Open Modern Project: Could not load project Message Appears

Products

• Clarity PPM On Premise

Issue/Introduction

Some project managers cannot open Modern projects.
The banner message is: Could not load the project.

The APP error contains the excerpts:
ERROR 2023-07-13 05:32:05,822 [ajp-nio-8011-exec-1579] ppm.rest (clarity:user:session:PPM_REST_API) An exception occurred while running API post process rules.
com.ca.ppm.rule.exception.RuleEngineException: Could not evaluate rules due to an internal error.
    at com.ca.platform.osf.object.rule.ODFRuleExecutor.executeRules(ODFRuleExecutor.java:131)

ERROR 2023-07-13 05:32:08,948 [ajp-nio-8011-exec-1631] rule.ODFRuleExecutor (clarity:user:session:PPM_REST_API) Exception occurred while executing blueprint rules for the object project instances
Exception executing consequence for rule "xxxxxxxxxxxxxxxxxxxx - group code: 00000004 - 1" in com.ca.ppm.rule.drools.template.rule: java.util.IllegalFormatConversionException: d != java.math.BigDecimal

ERROR 2023-07-13 05:32:14,533 [ajp-nio-8011-exec-1625] ppm.rest (clarity:user:session:PPM_REST_API) An exception occurred while running API post process rules.
com.ca.ppm.rule.exception.RuleEngineException: Could not evaluate rules due to an internal error.

ERROR 2023-07-13 05:32:14,565 [ajp-nio-8011-exec-1607] rule.RuleOutcome (clarity:user:session:PPM_REST_API) Cannot save outcome of rule (00000004) for object (project), pk (8940846). Rule ran suseccfully but did not find the rule meta-data in cache.

Environment

Release : 16.1.1

Resolution

Based on the error:
ERROR 2023-07-13 05:32:14,565 [ajp-nio-8011-exec-1607] rule.RuleOutcome (clarity:user:session:PPM_REST_API) Cannot save outcome of rule (00000004) for object (project), pk (8940846). Rule ran suseccfully but did not find the rule meta-data in cache.

Clearing the browser/Clarity cache or restarting APP and BG services resolves the issue.