Cant Input Tags But Could Previously

hi there…

i have 7 different sites running off wordpress however i am only having a problem with 1 site https://www.streetmotion.co.za..

I could previously input tags per post and everything was fine however recently whenever i want to add a tag to the post i can’t.. I am only having a problem with this site itself and not the other 6..

I have reinstalled wordpress a few times on the site but that has not helped either…

Can any1 help rectify this issue please…