This used to happen to me (in Montreal, so perhaps not the same as your experience) with SPCA. I emailed them and told them very politely that I donate on my ow

This used to happen to me (in Montreal, so perhaps not the same as your experience) with SPCA. I emailed them and told them very politely that I donate on my own schedule, that I appreciate the work they do, and to please stop wasting their (my) money asking me for more donations. They replied thanking me for the e-mail and saying that they had removed me from their mailing list.