This is intended behavior to prevent the application (SUD) slowdown. This may happen due to...
- Collector overload during SUD/agent start up (collector may be handling other agents or many agents might have started at the same time)
- Or the network/bandwidth between the agent and the collector is bad or interrupted.
If it is a temporary issue, just restarting the application (SUD/agent) should solve this issue. The collector health may be checked for its optimal operations (Collector health dashboard can be used)