Mortgage question

I live in Texas and my mortgage company just sent me a legal form which was also sent to my attorney and my chapter 13 trustee asking for relief from stay against property and waiver of 30 day requirement. In all this legal paper they claim I did not make my april 2001 house payment. I had a problem making the payment because I made the payment through my ATM machine (as I have done int he past with no problems) but my bank mistakenly deposited the money into my checking account so it did not go to the mortgage co. I have a checking and my son has a savings account at this bank. So I went ahead and triied to make the payment through my online bill pay. this further complicated the matter as I ended up having a charge that went through whch caused the payment to not be made. So I went ahead and sent them the payment via priority mail. I know they got the payment because I have looked at my mortgage statement online and this was credited to my account. What are they doing? i wrote a letter to the mortgage company explaining what had happpened whent the problem occured with my making my payment via my ATM aand have received no reply. I guess my getting this legal form is my reply???? Please help.

Thank you