irs payment plan

I have a payment plan that has been set up for years, as both my ex-husband and I owe in the thousands. It is direct pay on the 16th of every month. However, last month, only half the amount was taken out. I also logged into my irs online account and found that none of the payments were updated to the account from May, June, July, August, and the partial payment in September.  I set up and went to an appointment to find out what was happening. It appears that since he is the primary person listed on our returns, the money has been going directly to pay off anything that HE owes. The representative stated that I was secondary on the payment plan both, signed by both of us, with both SS#s on it. However, the payment plan doesn't show up on my online account. The direct pay is taken on time, every month, from MY account, which he deposits half of the payment.

As of today, the date of this month's payment, NOTHING has been taken for payment, even though there is an outstanding balance of the ENTIRE payment plan to honor both debts owed to the IRS. I don't want more penalties and interest accruing which will also show that no payment was made, resulting in a DEFAULT OF THE AGREEMENT!!!!  The payments have religiously been automatically taken on time every month for years with no issues, whatsoever. Please advise as to why this is occuring. I called the IRS today....waited for almost 1 and 1/2 hours to being abrubtly DISCONNECTED!!! HELP!!!!