Why can't I edit the additional Payment name?

[wcnpTI]

I had created the following label for this field on the additional info tab: "Consider making a donation if you cannot attend the event. Thank you." and there was no problem. Now I want to edit this to the following:
"Please consider making a donation of $25.00 or more to TWC. Thank you. " and I get the error: Please Enter a Valid Additional Payment Name". I've tried shortening it and that doesn't seem to make a difference. Can you please tell me what the issue is?

[CnP.Support.AM]

Good day @wcnpTI

Please note that special characters are not allowed in that field and we noticed that you are trying to enter the $ symbol in the text. Please remove the $ symbol and try to save it.

[wcnpTI]

That did it! Thanks so much.