Hi,
In Exchange 2019, Microsoft re-engineered search using Bing. The search indexes are now within the database itself. As the index data is now within the database, normal log shipping includes the database and search data in a single replication and the index is always up to date on all database copies.
I would suggest you try the following steps
- Check if the disks has sufficient free space available
- Use a different browser and see it is fine
- Restart the following services and try again
"Microsoft Exchange Search"
"Microsoft Exchange Search Host Controller"