SAP EHS Phrase Error

This Specific Phrase (EQUIS -100000000001098) was created in system long time back. I had to edit something on that phase so I went to cg12 to edit this Phrase. But I found error on this phrase we never notice earlier. When this phrase was created, the first word of the phrase, "The" was incorrectly entered as "THe". Looks like Sap interprets the TH as a tag and not as part of phrase. So, Sap is not allowing me to correct error.First few lines of phrase are grey-out and cannot edit

When I try to select the grey-out text, I get “A template is selected by line” message, which I cannot edit.

Will also receive an “Unable to call PC editor (unknown paragraph format <TH>) message.

Please need help!

Thanks