Hi Omar,
See if there are enough agents defined in the NX_ROOT\NX.env file for MAX_DBAGENT values. Default you will have 6 and if you might want to increase the DBAGENT value in multiples of 3 and check the behavior.
Note: Below are the values from an OTB environment and need to revisit based on each environment.
# Set NX_MAX_DBAGENT to a number. This will be the maximum number of generic agent executable that
# the provider will run at a time.
# Set NX_MIN_DBAGENT to 6
@NX_DOMSRVR_MODE=MP
@NX_MIN_DBAGENT=6
@NX_MAX_DBAGENT=6