harassment from husband's ex

My husband and I live in Utah. We have been married for four years. His ex-wife has been harassing us for four years by calling his work or our home if her alimony and child support checks are not there on the 5th and 20th of each month. She calls on the 5th, 6th, 7th, etc. leaving rude messages or talking rudely to him at work or at home. If he hangs up, she calls back, sometimes 25 times. She is even rude to his co workers if they will not put her call through. We cannot block her number as it is a cell phone. However, we need to pay on his paydays, every other Friday, which may not be the 5th or the 20th. We have never missed a payment, but sometimes they are on the 3rd, or the 8th, or the 18th, or the 24th, etc. depending on his paydays. We pay her twice a month. Can we stop this harassment?

[vrzirn]

If you skimp for awhile and save up the alimony for a month in advance you will be able to pay her on time.