(b) has caused disruption at the premises of the contracting authority. 

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.4.9  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. 

II.4.10  The contractor must immediately inform the Contracting authority of any changes in the exclusion situations as declared, according to Article 137 (1) of Regulation (EU) 2018/1046. 

## II.5.1 Form and means of communication 

## II.5. COMMUNICATION BETWEEN THE PARTIES 

Any communication of information, notices or documents under the contract must: 

(a) be made in writing in paper or electronic format in the language of the contract; 

(b) bear the 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 . 

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. 

The parties agree that any communication made by email has full legal effect and is admissible as evidence in judicial proceedings. 

## II.5.2 Date of communications by mail and email 

Any communication is deemed to have been made when the receiving party receives it, unless this contract refers to the date when the communication was sent. 

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. 

Mail sent to the contracting authority is deemed to have been received by the contracting authority on the date on which the department responsible referred to in Article I.8 registers it. 

Formal notifications  are considered to have been received by the receiving party on the date of receipt indicated in the proof received by the sending party that the message was delivered to the specified recipient. 

## II.5.3 Submission of e-documents via e-PRIOR 

If provided for in the special conditions, the exchange of electronic documents (e-documents) such as invoices between the parties is automated through the use of the e-PRIOR  platform. This platform provides two possibilities for such exchanges: either through web services (machine-to-machine connection) or through a web application (the supplier portal ). 

The contracting authority takes the necessary measures to implement and maintain electronic systems that enable the supplier portal  to be used effectively. 

