Sent all emails to archive, 2012 to 2014 ok. 2015 to 2019 lost

I recently started using Thunderbird and have been impressed with the ease of use it has allowed for me to have multiple emails in one place. But I have hit a problem with my hotmail account. I deleted all unwanted emails and then I sent the rest to an archive folder I had manually created, then I realised there was an archive folder within the hotmail account (still within thunderbird) so I selected all the emails and drag and dropped them into the proper archive folder. This created a list of folders ranging from 2012 to 2019. Everything from 2012 to 2015 seems ok but everything from 2015 to the present is not showing and I'm not sure why, I have read through some other forum posts and managed to get into folders but am not confident in changing anything in case I make it worse. I'll attach a screenshot of the archive folder details. If anyone can help it would be greatly appreciated. Print screen was not working for some reason so a pic was taken.