Odd email problem.

[#1]

At one time when email arrived in my inbox it appeared in date order with the most recent and unread emails appearing at the top of the list.
For some unknown reason mail is now arriving in between  older email that has already been read.
Not sure if this is some error on my part but would be grateful for advice on a fix for this problem.
To give a more clearer example I might have 4 previously opened older emails then one new email appears under that one with the current date then 5 or 6 older opened email then a further one or two new emails.
In short I have to check my whole email box for new emails that could be anywhere.

[#2]

This might seem a silly question, but what program do you run to look at your emails and on what device/operating system?

[#3]

So, what field are you sorting on - title, sender.....?

[#4]

Quote from: HPsauce

This might seem a silly question, but what program do you run to look at your emails and on what device/operating system?

I have 2 email programs, one is Gmail that works fine with no problem and the other one is Plusnet email which is the one I am having this odd problem with.
I am using a desktop computer running Linux Mint 17 although I sometimes access my email using a Samsung tablet.
PeeGee,
Not sure about the sort field, didn't even know there was one but that sounds like a logical explaniation although I do not recall making any type of alterations in the settings, will certainly look into that.

[#5]

Quote from: gleneagles

I have 2 email programs, one is Gmail that works fine with no problem and the other one is Plusnet email

Those are email SERVICES, not programs. To get pedantic, what do you RUN or CLICK ON to access your Plusnet email?.

[#6]

Firefox.

[#7]

And then within Firefox, what? We're getting closer. 
e.g. Are you going to a PlusNet mail interface (webmail?) or via another service (there are loads, even Gmail will do it) that accesses your PN mailbox for you? Post the URL you use here.
If it's PN webmail I never use that so can't advise, but others presumably will.

[#8]

I go on to plusnet's main site and select webmail from the menu which includes connection settings etc, if I select webmail it does not matter if I am logged on to the main PN site or not I still get access to the login window for webmail.
Hope this is the info you need.

[#9]

Quote from: PeeGee

So, what field are you sorting on - title, sender.....?

I believe the PN webmail allows you to sort on any of the columns, hopefully someone who uses it can advise, but usually the convention is that you just click on the relevant column heading.

[#10]

As summised by HPSauce,  PNs webmail allows sorting by clicking on the column header, the column used for sorting is highlighted in a darker grey than the rest,  and a little arrow indicates ascending or descending order.

[#11]

Thanks for that, have found the list giving the various options but the selected options seem fine, however I selected apply without making any changes but the problem persists.
Fortunately I only use webmail for a few things so it's not a major problem but just out of interest is it possible to delete or change this mail box and start from scratch again, I accept everything in my webmail in box would be lost ?

[#12]

Under the topic of," Advantages of a Plusnet email account" Townman mentions a possible problem if using different devices with a POP account, could this have any bearing on the problems I am having ?
Apologies if this has been worded badly but I think you can see what I am trying to ask.

[#13]

POP3 mail collection is only a concern if you are using a device that runs a mail application and this downloads your email.  You have said that you are using webmail so POP3 is of no consequence.
The webmail interface is very simple - If you click on 'Date' as per kmilburn's screengab, the email will sorted by date.  Each time you click on Date the display will toggle between oldest or newest received being first.
If this doesn't fix it, click on the icon to the left of 'Subject' and make sure that 'List' is selected and not 'Thread'.  Save any changes to clear the popup window.
HTH

[#14]

Thanks for the responses, date and list were showing.
The last couple of emails that came through appeared at the top of the list but I will need to give it a few days to be sure it's ok but that's wishful thinking as all settings/options were set as expected.