Like all software, PTS 5 is not immune to occasional temporary performance issues.

Symptoms

Various functions of the PTS application take an unsatisfactory amount of time to load or to process.

Common causes

The database has grown large and the data has become fragmented.
Printer settings are not optimal.
Other software on a shared server is hogging resources.
An unoptimised or expensive third party query is hitting the PTS database.
The server/s only meet the bare minimum hardware requirements.
PTS is trying to connect to reach tmsinsight.com for support contract and software licensing notifications, but your PTS server has no access to the internet.

Index the PTS database.
Turn off bi-directional support. (Please do not underestimate the performance impact of this setting even if you have never heard of it before)
Use a resource monitor or the SQL performance dashboard to identify the application at fault and then contact the manufacturer.
Use SQL performance dashboard to identify the expensive query and have IT or the manufacturer optimise it and/or reduce its frequency. (This issue seems to be becoming more common, please test your queries for performance at scale before rollout)
Consider upgrading your server hardware to the recommended PTS 5 specification.