Transaction Series Naming issue

I wrongly updated the Journal Series number format with JE19/### instead of JE19.###. The system now refuses to change the format desired. Even if I change the format to JE19.###, it uses JE19/###. How do I fix this problem. Has the / have a particular meaning in this instance?

I have tested now, it’s ok with me!
Just change the naming series of selected doctype and don’t forget to Update

Thank you Omar. Did you simulate this problem with a / then tried to re-name with . ? Example enter format as JE19/###. It will show this, but then change to JE19.###. For me it every time comes back with JE19/### format.