Optonline.net email going straight to trash on iPad mini

Been having this issue since right before Xmas...Have an iPad 4 mini running iOS 13.3...using the Apple Mail program in order to get email...have spoken to Optonline.net Helpdesk but they are not being very helpful in resolving the problem...have removed and reset the email several times with always the same result...instead of mail going into Inbox, goes into Trash...no filters are set, so the mail should come straight to the Inbox..the problem is with my wife's email...when I created an email account under my email address on her iPad 4 mini and there was no issue...mail started pouring in to the Inbox...did not fuss with port numbers or filters when I logged in...and everything just worked...I think the problem is on Optonline's end...not on the client email program...looking for any thoughts on this...thanks...and Happy New Year...