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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Receivable being later than the Collection Period immediately preceding the Final Maturity Date for the latest maturing Class of Notes, (ii) cancels a Receivable or reduces or waives (including with respect to any Upgrade Offer) the remaining Principal Balance under a Receivable or any portion thereof and/or as a result, the monthly payments due thereunder, or (iii) modifies, supplements, amends or revises a Receivable to grant the Obligor under such Receivable a contractual right to upgrade the related Device, it will acquire the affected Receivable solely as described under Section 3.3, unless it is required to take the action by Law. In addition, if the Marketing Agent or the Servicer (x) applies a payment or grants a credit to an Obligor with respect to cancellations, prepayments or invoicing errors the Servicer may apply such credits either directly to the applicable device payment plan agreement or in accordance with its customary payment application procedures set forth above and (y) applies a payment or grants a credit to an Obligor under a Receivable in connection with an Upgrade Offer as set forth in Section 3.12(b), the Servicer will apply such credits directly to the applicable device payment plan agreement and will not apply such credits in accordance with its customary payment application procedures set forth above. 8 Source: VERIZON ABS LLC, 8-K, 1/23/2020 (c) Maintenance of Security Interests in the Receivables. The Servicer will maintain perfection of the security interest of the Issuer and the Indenture Trustee in each Receivable. (d) No Impairment. The Servicer will not impair in any material respect the rights of the Issuer or the Noteholders in any Receivable except as permitted by this Agreement. (e) Assignment for Enforcement. Effective as of the related Cutoff Date, the Receivables are assigned to the Servicer solely for the purpose of permitting the Servicer to perform its servicing and administrative obligations under this Agreement, including the start or pursuit of or participation in a legal proceeding to enforce its rights or remedies with respect to a Receivable or such other Proceeding otherwise related to a Receivable. If in a legal proceeding it is held that the Servicer may not enforce its rights or remedies with respect to a Receivable on the grounds that it is not a real party in interest or a holder entitled to enforce rights or remedies with respect to the Receivable, the Issuer will, at the Servicer's expense and direction, assign the Receivable to the Servicer solely for that purpose or take steps to enforce its rights and remedies with respect to the Receivable, including bringing suit in the names of the Indenture Trustee, the Noteholders and the Issuer. (f) Powers of Attorney. The Issuer appoints the Servicer as the Issuer's attorney-in-fact, with full power of substitution to exercise all rights of the Issuer for the servicing and administration of the Receivables. This power of attorney, and all authority given, under this Section 3.2(f) is revocable and is given solely to facilitate the performance of the Servicer's obligations under this Agreement and may only be used by the Servicer consistent with this Agreement. On request of the Servicer, the Issuer will furnish the Servicer with written powers of attorney and other documents to enable the Servicer to perform its obligations under this Agreement. (g) Release Documents. The Servicer is authorized to execute and deliver, on behalf of itself, the Issuer, the Indenture Trustee and the Noteholders any documents of satisfaction, cancellation, partial or full release or discharge, and other comparable documents, for the Receivables. (h) Enforcement of Receivables Under an Upgrade Offer. If an Obligor accepts an Upgrade Offer with respect to a Receivable but fails to satisfy the required terms and conditions related to such Upgrade Offer, the Servicer agrees to (i) not waive any amounts due by such Obligor under the related Receivable and pursue its Servicing Procedures against such Obligor in respect of the related Receivable until all amounts due under the related Receivable are received and (ii) enforce, on behalf of the Issuer, any rights and obligations under the related Receivable. Section 3.3 Servicer's Acquisition of Receivables. (a) Acquisition for Servicer Modifications. If extensions, modifications, amendments, cancellations or waivers of Receivables or any terms thereof are made that would require such Receivables to be acquired under Section 3.2(b), the Servicer will acquire all such Receivables as set forth in Section 3.3(d). (b) Acquisition for Breach of Servicer's Obligations. If a Responsible Person of the Servicer receives written notice from the Depositor, the Issuer,
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Extract the exact clause related to "Warranty Duration" from the excerpt above.

assistant: Not found.