Internet service payment posting date: please help!

Thank you for replying, I should have clarified: I'm a long term customer and this is a unique, temporary situation as the payments are being made/sent by my employer.
Last month the payment was received but not posted to my account (for approx 3.5 weeks)  and my service was disconnected.
I was fortunate enough to finally contact someone in customer service, a supervisor I believe and he immediately posted the payment restoring my service but I don't have his name or contact information I'm trying to avoid this from occurring again! 

I do apologize @nwgirl73, but that is not something we can do one our end. We will need to wait for the payment to post before we can look at restoring services. We recommend in order to avoid any possible service interruption, that online payments be made. Things such as holidays, weather delays, mail delays, and more can effect the delivery and processing time of mailed in payments. If the account does get suspended for non-payment, we recommend reaching out to our billing team to review any possible options.

As always, you can check to see if the account is eligible for a payment arrangement by visiting our 'Set up a payment arrangement for your Xfinity balance' support page which may help secure services while you wait for the mailed in payment to be delivered and processed.

My service was restored last month and my payment is not late - my question was how to ensure the payment is posted to my account once it clears as I indicated there was a delay of 3 1/2 weeks despite clearing immediately. 
If I understand correctly: customer service cannot assist me (?) there is no way to review my account to identify the wonderful Xfinity employee who resolved the issue so quickly? I'd like to contact him/them it was just a few weeks ago and he mentioned helping to prevent the same thing from happening this month ie: the payment not posting automatically to my account, resulting in my service being disconnected. 

I've obviously tried calling customer service, co-workers & relatives convinced me this was the best & only way to resolve this type of unique situation ... what am I missing? 

Payments made by check may not be reflected in the Xfinity app until the check has cleared. Credit card payments require verification from the clearing house @nwgirl73.

Payments may take one to three days before they are credited. Pending payments will be reflected in the app. If your service has been suspended due to non-payment, your service will be restored once you've made the payment. You can confirm your payment has gone through successfully by opting to get a payment confirmation alert in your account, for any payment option you used.