Can my gastric sleeve be redone after 7 years, or what is my next option?

Surgery is never 100%, and patients can experience weight regain. You're not alone.
Try contacting your Bariatric Center that performed the original procedure and see what their recommendations are. You will most likely need an evaluation that will look at behavioral issues as well as possible mechanical causes. An UGI Swallow X-ray will help determine appropriate options.
Most surgeons offer revisions in what they are most comfortable. Be sure to evaluate the surgical options of (1)Re-sleeve, (2)Gastric Bypass, and (3)Duodenal Switch.

If you have gained the weight, the reason needs to be investigated.
If you eating large volumes, then Re-Sleeve is an option.
If you still have restrictions then changing to a more malabsoptive procedure like Gastric Bypass should be considered.
If you still eating high calorie diet, then you need a more invasive procedure with higher complication rate like Bilio-pancreatic diversion.