Leak at hst input shaft seal

[Zork]

Any help would be greatly appreciated. I have a TYM T234 hst. Great little tractor.. I believe we bought it in 2018 or there about. Last year, I noticed very slow leak. From what seemed to be the input shaft to the HST just above the filter. Was very slow so I put it off.. I definitely thought that it was the input shaft seal. This Spring it got noticeably worse. So I took the body off and replaced the input shaft seal. I did it very carefully.. I put the thing back together and the leak is the same. I took out the section filter.It did not look bad.There was some debris I took out the suction filter. It did not look bad. There was some debris on it .when I took the first shaft seal out, It did not look bad. But I replaced it anyway. Could there be Any other causes to this issue? From what I have read, people have said it could be a pressure issue. Any ideas or a way to troubleshoot this? I would really appreciate it, thanks!

I missed some of this. If the input shaft is damaged at the seal location with a groove it will likely leak again if the seal depth isn’t seated to an undamaged portion of the shaft or if the shaft is not dressed with sand paper/emery cloth to smooth the groove- or you will need to install a sleeve and the new seal.