I created a beta release (11.2.0 beta 1). In this release I try to solve an issue which I encountered a couple of times. Sometimes the PostNL API doesn’t return any data (5xx error) or is unreachable. This will break the sensor and therefor the lovelace. I try to solve this by adding a retry strategy. I also changed the behaviour in retrieving data (using async now). This will improve the start time of the integration.
Please test the beta release and let me know if there are (no) issues 
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