I hate to burst your bubble and break it to you, but "Sola Scriptura" is a myth. Anyone who claims to be "Sola Scriptura" is either ignorant or a liar. If you believe that "all I need is my Bible," then please tell me who wrote the first book that appears in our New Covenant. Matthew? Why do you believe that? Where in the book does it identify the author? The names at the top of the books are not part of the original manuscripts. Paul did not write "1 Corinthians" at the top of his letter to the Corinthians (which is actually his second letter; the first is lost to us). So why do you believe that the first book was written by Matthew? the second book by Mark? the third book by Luke? the fourth book by John? Etc.
The reason you believe these things is because the early Christians said that is who wrote them. So accepting that is Extra Scriptura, it is outside of Scripture. If you want to truly be "only Scripture," then you need to remove "Matthew," "Mark," "Luke," and "John" out of our Bibles. Call them First Gospel, Second Gospel, Third Gospel, and Fourth Gospel instead. Same goes for First John Second John, and Third John. Call them First Anonymous Letter, Second Anonymous Letter, and Third Anonymous Letter instead.
Why do you believe the 27 books of our New Covenant are canon? The apostles did not hand their disciples a completed New Covenant. The first complete New Covenant did not appear until about the end of the 3rd century. For the first 20 years after Pentecost, not a single word of the New Covenant had been written. It took 40 years for the entire New Covenant to be written. So why do you believe the 27 books we have are supposed to be there? Again, you need to go outside of Scripture. The early Christians compiled lists of these books. These 27 books were consistent.
Even the Reformers, who touted "Sola Scriptura" as their battle cry, did not follow their profession. The Reformers made sure their readers would not have "Sola Scriptura" by inserting prefaces to each book and chapter of the Bible, steering the reader's attention away from parts that did not fit their theology. The marginal notes that "explain" the Bible make void the claim of "Sola Scriptura." The Geneva Bible was horrendous for this. This is the only good thing about the King James Version; the lack of running commentaries.
Evangelicals are no closer to "Sola Scriptura" today than they were in the sixteenth century. Evangelicals blindly prefer to purchase interpretative "study" Bibles that willfully steer them away from "Sola Scriptura." I am not merely talking about the poor addition of chapters and verses, which distract the reader from the context and main intention of the author, or about cross reference systems that are the result of proof text methodology. Some Bibles are helpful, such as the Thompson-Chain Reference Bible or the Newberry Reference Bible. But most these "study" Bibles add human interpretations and biases alongside Scripture, giving man's words equal weight with Yahweh's, influencing the average reader by essentially making man's opinions equal to the inspiration of Scripture, which they are not!
When you are reading the epistles, you are hearing one side of a phone conversation. You are missing important context. Not to mention that you are missing what the authors said to their audience in person. When Paul says things like, "And you know what restrains him now, so that in his time he will be revealed," you and I do not know. You and I were not privy to those in-person conversations.
When you read First Corinthians and come across difficult-to-understand passages, how do you determine to figure out what they mean? You will not find the answers in "Sola Scriptura." You need to go Extra Scriptura. Ideally, you should go to the primary source. However, since we cannot ask Paul, and we cannot ask the Corinthians, who can we ask? We can look to the early Christians and see how they understood these passages and put them into practice. If you want to understand Scripture correctly, you need to listen to the early Christians!
Nobody uses "just the Bible alone"! Anyone who claims to is a liar. Do they make use of Bible commentaries? dictionaries? handbooks? lexicons? Do they read references on historical and culture backgrounds? Do they read Christian literature? Do they listen to sermons? All these things are Extra Scriptura, but not all of them are helpful. If you do not use any Bible aids whatsoever, and do not read or listen to anything else, but only read the Bible, then you could try to claim you use "just the Bible," but if you listen to a "pastor," then you are not.