Unable to sign in to Paramount+ Plus on Roku TV

dlhobbs62​   Not exactly sure what you mean by lock up, but I am having an issues with Paramount Plus today.  I am not able to watch and if I try to sign in, it asks me to purchase a subscription, but I have a subscription through my cable provider.  So, it may be some Paramount plus network issue today.  I would give it a day and see what happens.  Or you can contact customer service for P-plus, directly.