Contract number: ECHA/2020/666  (b) their participation in providing the services does not result in any employment or  contractual relationship with the contracting authority.  II.4.8  The contractor must ensure that the  personnel implementing the FWC and any  future replacement personnel possess the professional qualifications and experience  required to provide the services, as the case may be on the basis of the selection  criteria set out in the tender specifications.  (a) does not have the expertise required to provide the services; or  (b) has caused disruption at the premises of the contracting authority.  II.4.9  At the contracting authority’s reasoned request, the contractor must replace any  member of  personnel  who:  II.4.10 The contractor must record and report to the contracting authority any  problem that affects its ability to provide the services. The report must describe the  problem, state when it started and what action the contractor is taking to resolve  it.  (a) be made in writing in paper or electronic format in the language of the contract; (b) bear the FWC number and, if applicable, the specific contract number;  (c) be made using the relevant communication details set out in Article I.8; and  (d) be sent by mail, email or, for the documents specified in the special conditions,  via  e-PRIOR . 24  E-mail is deemed to have been received by the receiving party on the day of dispatch of  that e-mail, provided that it is sent to the e-mail address indicated in Article I.8. The  sending party must be able to prove the date of dispatch. In the event that the sending  party receives a non-delivery report, it must make every effort to ensure that the other  party actually receives the communication by email or mail. In such a case, the sending  party is not held in breach of its obligation to send such communication within a specified  deadline.  Any communication is deemed to have been made when the receiving party receives it,  unless this FWC contract refers to the date when the communication was sent.  The parties agree that any communication made by email has full legal effect and is  admissible as evidence in judicial proceedings.  If a party requests written confirmation of an e-mail within a reasonable time, the other  party must provide an original signed paper version of the communication as soon as  possible.  Any communication of information, notices or documents under the FWC must:  The contractor bears the cost of replacing its  personnel  and is responsible for any  delay in providing the services resulting from the replacement of  personnel .  II.5. COMMUNICATION BETWEEN THE PARTIES  II.5.1. Form and means of communication  II.5.2. Date of communications by mail and email 