Tags Reverting to Uppercase

Please help! I had a tag in a number of images that I’m trying to change..the format of the tag is Word1 Word2 and I’m trying to change it to word1 word2 with all lowercase letters…I change the data, press save and…it’s back to capital letters again – nothing I seem to do will allow me to change the tag to lowercase. I’ve even tried deleting it and putting something else in…then adding the lowercase tag back but it’s just not working and it’s totally ruining the look of my site =(

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