Unicom sent me a short message telling me that my available credit line is insufficient. What does 50 yuan mean?

It may be confirmed that your mobile phone is in arrears, and the excess after you call the phone bill is the available credit limit, so your mobile phone should be in arrears (for example, your mobile phone has been saved 100 yuan). Your 100 yuan has been used up. But you can still call, and the part you call is the available credit line, and everyone's available credit line is different. According to your situation, you may not be able to play after 50 or so. It's time to stop. For example, my available credit line for one month is 750, which means I can make a phone call without charge, and I can't make a phone call if my credit line exceeds 750, which is 750 yuan. If it reminds you that you owe money. Then I owe at least 750.