system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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a.m. - 2:00 a.m. 6:00 a.m. 12:00 midnight Cardbase Management System Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday 7:00 a.m. - 12:00 midnight Sunday 7:00 a.m. - 12:00 midnight CIS & Deposit System Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday 7:00 a.m. - 12:00 midnight Sunday 7:00 a.m. - 12:00 midnight Loan System Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday 7:00 a.m. - 12:00 midnight Sunday 7:00 a.m. - 12:00 midnight General Ledger Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday 7:00 a.m. - 12:00 midnight Sunday 7:00 a.m. - 12:00 midnight Information Desktop Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday 7:00 a.m. - 12:00 midnight Sunday 7:00 a.m. - 12:00 midnight Teller System Monday - Thursday 6:45 a.m. - 12:00 midnight Friday 6:45 a.m. - 12:00 midnight Saturday 6:45 a.m. - 12:00 midnight Sunday 6:45 a.m. - 12:00 midnight IRS Government Reporting System Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday 7:00 a.m. - 12:00 midnight Sunday 7:00 a.m. - 12:00 midnight Account Analysis Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday 7:00 a.m. - 12:00 midnight Sunday 7:00 a.m. - 12:00 midnight Safe Box Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday - Sunday 7:00 a.m. - 12:00 midnight VRU 1 Monday - Thursday 12:01 a.m. - 12:00 midnight Friday 12:01 a.m. - 12:00 midnight Saturday 12:01 a.m. - 12:00 midnight Sunday 12:01 a.m. - 2:00 a.m. 6:00 a.m. 12:00 midnight Bank Control Monday - Thursday 7:00 a.m. - 12:00 midnight Friday 7:00 a.m. - 12:00 midnight Saturday 7:00 a.m. - 12:00 midnight Sunday 7:00 a.m. - 12:00 midnight Account Reconciliation Monday - Thursday 7:00 a.m. - 6:45 p.m. Friday 7:00 a.m. - 9:30 p.m. Saturday 7:00 a.m. - 4:30 p.m. Deposit Teller1 Monday - Thursday 12:01 a.m. - 12:00 midnight Friday 12:01 a.m. - 12:00 midnight Saturday 12:01 a.m. - 12:00 midnight Sunday 12:01 a.m. - 2:00 a.m. 6:00 a.m. 12:00 midnight _____________________ 1 M&I's objective is to provide 24 x 7 hour availability for these systems. M&I does however need to perform regular technical maintenance (e.g., NCP maintenance), CPU IPLs, DASD installs, IHS gens, etc.). This type of maintenance is performed between 2:00 a.m. and 6:00 a.m. CST/CDT. These activities may result in system downtime during this window. C. Processing Time. M&I will process transactions in an average of 2.5 seconds for teller transactions (not to exceed six (6) seconds for five percent (5%) of all transactions per month) and in an average of three point five (3.5) seconds (not to exceed seven (7) seconds for five percent (5%) of all transactions per month) for bank operations CRT transactions as measured over a calendar month, from the time the transaction is sent by the Customer's controller or gateway to the time the processed data is returned to the Customer's controller or gateway. Should M&I not be able to perform in accordance with the Performance Standards because Customer failed to acquire network or equipment recommended by M&I, or such additional network or equipment as may be reasonably necessary based on the circumstances, M&I shall notify Customer in writing and Customer shall either acquire such network and/or equipment or accept the response time that is achieved. D. Service Level Credits. REDACTED 10. MODIFICATION OR TERMINATION OF SERVICES 10.1 Modifications to Services. M&I may modify, amend, enhance, update, or provide an appropriate replacement for the software used to provide the Services, or any element of its systems at any time to: (i) improve the Services or (ii) facilitate the continued economic provision of the Services to Customer or M&I, provided that the functionality of the Services is not materially adversely affected. 10.2 Partial Termination by M&I. M&I may, at any time, withdraw any of the Services (other than the Core Services) upon providing ninety (90) days' prior written notice to Customer. M&I may also terminate any of the Services immediately upon any final regulatory, legislative, or judicial determination that providing such Services is inconsistent with applicable law or regulation or upon imposition by any such authority of restrictions or conditions which would detract from the economic or other benefits to M&I or Customer to any element of the Services.
"""

Extract the exact clause related to "Covenant Not To Sue" from the excerpt above.