Unresolved Usage Limit increase

I am writing to express my extreme dissatisfaction with the ongoing failure to increase my usage limit. Despite numerous calls to your call center since December 23rd, my issue remains unresolved. Each time I contact customer service, I am met with an error message preventing the limit increase. Furthermore, my requests to speak with a manager are consistently denied. This lack of resolution and escalation options is unacceptable. My reference number for this issue is BO***. I kindly request that this matter be addressed urgently and that a manager contact me directly to resolve this issue.