I was doing a docket case review for my sister recently. I decided to do one for myself and found that a company filed a case against me 3 years ago.. the case status is open but I was never summoned to court... The statuate of limitations is up very soon on this account.. I disputed it with company and they continued to add late charges and interest to a late fee that didn't exist according to their records... Is it usual that a case sit on court files for that length of time and no summons be issued

Yes it's unusual. Most courts have a mechanism to review stale cases like this and dismiss them when nothing has been done for that long a time.

Are you sure no summons was issued? Normally a summons will be issued at the same time the case is filed.

A statute of limitations bars a suit from being filed. Since this suit was filed, they would, strictly speaking, have the argument that the SOL doesn't apply no matter how long they take to get service of process.

I suggest you let sleeping dogs lie.