avoid concurrent access of postgres db - postgresql

Question

We have two .net services (.Net core console applications) which are accessing a postgres db table.
Service 1 inserts some 500 rows every 1 minute. It runs as a background thread.
Service 2 reads data from the same table continuously. There is an MQTT publisher which keeps reading data from this table when any new data is requested. This also happens very frequently i.e atleast 4/5 times a minute.
We are getting "FATAL: sorry, too many clients already " error.
What I am assuming is since write and read is happening simultaneously too frequently, the connection is not getting dispose properly.
Is there a way to avoid read whenever a write is happening.
EDITED
Thanks for the reply.. I know some connection pooling is happening but not sure where.. so my question was how to avoid concurrent access of postgres db..
Was not sure what part of code I can post to make the question clear
I am having using clause on dbcontext and also disposed like the below..
This is retrieval section
using (PlatinumDBContext platinumDBContext = new PlatinumDBContext())
{
try
{
var data = platinumDBContext.TrendPoints.Where(x => ids.Contains(x.TrendPointID) && x.TimeStamp >= DateTime.Now.AddHours(-timeinHours));
result = data.Select(x => new Last24hours
{
Label = x.TrendPointID.ToString(),
Value = (double)x.TrendPointValue,
time = x.TimeStamp.ToString("MM/dd/yyyy HH:mm:ss")
}).ToList();
}
catch (Exception oE)
{
}
finally {
platinumDBContext.Dispose();
}
}
This is the insertion section
using (PlatinumDBContext platinumDBContext = new PlatinumDBContext())
{
try
{
foreach (var point in trendPoints)
{
if (point != null)
{
TrendPoint item = new TrendPoint();
item.CreatedDate = DateTime.Now;
item.ObjectState = ObjectState.Added;
item.TrendPointID = point.TrendID;
item.TrendPointValue = double.IsNaN(point.Value) ? decimal.MinValue : (decimal)point.Value;
item.TimeStamp = new DateTime(point.TimeStamp);
platinumDBContext.Add(item);
}
}
platinumDBContext.SaveChanges();
}
catch (Exception ex)
{
}
finally
{
platinumDBContext.Dispose();
}
}
Regards,
Geervani